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ZOOLOGICA
6 6
SCIENTIFIC CONTRIBUTIONS
OF THE
NEW YORK ZOOLOGICAL SOCIETY
VOLUME XXVI 1941
Numbers 1-30
PUBLISHED BY THE THE ZOOLOGICAL PARK,
SOCIETY NEW YORK
NEW YORK ZOOLOGICAL SOCIETY
General Office: 630 Fifth Avenue, New York City
OFFICERS
President, Fairfield Osborn First Vice-President, Alfred Ely
Chairman, Executive Committee & Second Vice-President, Laurance S. Rockefeller
Treasurer, Cornelius R. Agnew
General Director, Zoological Park and Aquarium, Allyn R. Jennings Assistant General Director, Harry Sweeny, Jr.
Zoological Park
Raymond L. Ditmars, Curator of Reptiles and Insects Lee S. Crandall, Curator of Birds Claude W. Leister, Curator of Mammals and Educational Activities Leonard J. Goss, Curator of Health William Bridges, Editor and Curator of Publications
Aquarium in the Zoological Park
Charles M. Breder, Jr., Director Christopher W. Coates, Aquarist Ross F. Nigrelli, Pathologist G. M. Smith, Research Associate in Pathology Homer W. Smith, Research Associate in Physiology Myron Gordon, Research Associate in Genetics
Department of Tropical Research
William Beebe, Director John Tee-Van, General Associate Gloria Hollister, Research Associate Jocelyn Crane, Technical Associate
Consultant, Jean Delacour
SCIENTIFIC STAFF
Editorial Committee
Fairfield Osborn, Chairman
Allyn R Jennings William Beebe Charles M. Breder, Jr.
Harry Sweeny, Jr Jean Delacour William Bridges
CONTENTS.
PAGE
Part 1. May 26., 1941.
1. A New Crayfish from San Luis Potosi, Mexico. (Decapoda, Astacidae). By
Horton H. Hobbs, Jr. (Text-figure 1) 1
2. A New Corydoras from Brazil. By F. R. LaMonte 5
3. Notes on Plumage Changes in the Bald Eagle. By Lee S. Crandall. (Plates
I-IV) 7
4. External Characters of Six Embryo Nurse Sharks, Ginglymostoma cirratum
(Gmelin). By William Beebe. (Plates I & II; Text-figures 1-4) 9
5. A Papillomatous Disease of the Gallbladder Associated with Infection by Flukes,
Occurring in the Marine Turtle, Chelonia mydas (Linnaeus). By G. M. Smith, C. W. Coates & R. F. Nigrelli. (Plates I-IV; Text-figure 1) . . . . 13
6. Eastern Pacific Expeditions of the New York Zoological Society. XXIII.
Polychaetous Annelids from the West Coast of Mexico and Central America.
By Aaron L. Treadwell. (Text-figures 1-21) 17
7. Plankton of the Bermuda Oceanographic Expeditions. X. Polychaetous An-
nelids from Bermuda Plankton, with Eight Shore Species, and Four from
Haiti. By Aaron L. Treadwell. (Text-figures 1-9) 25
3. Caudal Skeleton of Bermuda Shallow Water Fishes. V. Order Percomorphi:
Carangidae. By Gloria Hollister. (Text-figures 1-20) 31
). Description of an Egg of the Long-tailed Bird of Paradise. By Lee S. Crandall.
(Plate I) 47
). On the Uterine Young of Dasyatus sabinus (LeSueur) and Dasyatus hastatus (De Kay). By C. M. Breder, Jr., & Louis A. Krumholz. (Text-figures 1 & 2) . ' 49
11. Additional Social and Physiological Aspects of Respiratory Behavior in Small
Tarpon. By Arthur Shlaifer 55
12. Notes on Mexican Snakes of the Genus Trim ere surus. By Hobart M. Smith. . 61
Part 2. September 8, 1941.
13. The Life History and Bionomics of the Trematode, Zygocotyle lunata (Param-
phistomidae). By Charles H. Willey. (Plates I-IV) 65
14. Eastern Pacific Expeditions of the New York Zoological Society. XXIV.
Fishes from the Tropical Eastern Pacific. [From Cedros Island, Lower California, South to the Galapagos Islands and Northern Peru.] Part 1. Lancelets and Hag-fishes. By William Beebe & John Tee-Van. (Text- figures 1 & 2) 89
15. Eastern Pacific Expeditions of the New York Zoological Society. XXV.
Fishes from the Tropical Eastern Pacific. [From Cedros Island, Lower California, South to the Galapagos Islands and Northern Peru.] Part 2. Sharks. By William Beeb^ & John Tee-Van. (Plates I & II; Text- figures 1-34)
93
PAGE
16. Correlations Between Structural Eye Defects and Behavior in the Mexican
Blind Characin. By Charles M. Breder, Jr., & Edward B. Gresser. (Plates I— IV ; Text-figures 1 & 2) 123
17. On the Species of Otus scops. By Jean Delacour. (Text-figures 1-10) 133
18. A New Genus of Kaleege Pheasants. By Marquess Hachisuka 143
Part 3. October 31, 1941.
19. Eastern Pacific Expeditions of the New York Zoological Society. XXVI.
Crabs of the Genus Uca from the West Coast of Central America. By Jocelyn Crane. (Plates I-IX; Text-figures 1-8) 145
20. Eastern Pacific Expeditions of the New York Zoological Society. XXVII. A
Study of Young Sailfish ( Istiophorus ). By William Beebe. (Plates I-V; Text-figures 1-9) 209
21. On the Reproduction of Opsanus beta Goode & Bean. By Charles M. Breder,
Jr. (Plates I & II) 229
22. On the Reproductive Behavior of the Sponge Blenny, Paraclinus marmoratus
(Steindaehner). By Charles M. Breder, Jr. (Plates I— III ; Text- figure 1 ) 233
23. The Chromatophores of Fundulus hetcroclitus in Polarized Light. By A. M.
Shanes & Ross F. Nigrelli. (Plates I— III) 237
24. New Races of Alaudidae and Timaliidae from Northern Thailand. By H. G.
Deignan 241
25. Respiratory Behavior in Fishes Not Especially Modified for Breathing Air
Under Conditions of Depleted Oxygen. By Charles M. Breder, Jr. (Plate I) 243
26. Eastern Pacific Expeditions of the New York Zoological Society. XXVIII.
Fishes from the Tropical Eastern Pacific. [From Cedros Island, Lower California, South to the Galapagos Islands and Northern Peru.] Part 3. Rays, Mantas and Chimaeras. By William Beebe & John Tee-Van. (Plates I-IV ; Text-figures 1-40) 245
27. Erotylidae of Kartabo, Bartica District, British Guiana. (Coleoptera.) By
C. H. Curran. (Plate I; Text-figure 1) 281
Part 4. December 29, 1941.
28. Further Studies on the Light Sensitivity and Behavior of the Mexican Blind
Characin. By C. M. Breder, Jr., & Edward B. Gresser. (Plate I; Text-figures 1 & 2) 289
29. Eastern Pacific Expeditions of the New York Zoological Society. XXIX. On
the Growth and Ecology of Brachyuran Crabs of the Genus Ocypode. By Jocelyn Crane. (Plates I & II; Text-figures 1-7) 297
30. High Speed Photographs of Flying Fishes in Flight. By H. E. Edgerton &
C. M. Breder, Jr. (Plates I-VIII) 311
Index to Volume XXVI 315
ZOOLOGICA
SCIENTIFIC CONTRIBUTIONS
OF THE
NEW YORK ZOOLOGICAL SOCIETY
0-
VOLUME XXVI Part 1
Numbers 1-12
- 'h»
PUBLISHED BY THE SOCIETY THE ZOOLOGICAL PARK, NEW YORK
May 26, 1941
CONTENTS
PAGE
1. A New Crayfish from San Luis Potosi, Mexico. (Decapoda, Asta-
cidae). By Horton H. Hobbs, Jr. (Text-figure 1) 1
2. A New Corydoras from Brazil. By F. R. LaMonte 5
3. Notes on Plumage Changes in the Bald Eagle. By Lee S. Cran-
dall. (Plates I-IV) 7
4. External Characters of Six Embryo Nurse Sharks, Ginglymostoma
cirratum (Gmelin). By William Beebe. (Plates I & II; Text- figures 1-4) 9
5. A Papillomatous Disease of the Gallbladder Associated with In-
fection by Flukes, Occurring in the Marine Turtle, Chelonia my das (Linnaeus). By G. M. Smith, C. W. Coates & R. F. Nigrelli. (Plates I-IV; Text-figure 1) 13
6. Eastern Pacific Expeditions of the New York Zoological Society.
XXIII. Polychaetous Annelids from the West Coast of Mexico and Central America. By Aaron L. Treadwell. (Text-figures 1-21) 17
7. Plankton of the Bermuda Oceanographic Expeditions. X. Poly-
chaetous Annelids from Bermuda Plankton, with Eight Shore Species, and Four from Haiti. By Aaron L. Treadwell. (Text-figures 1-9) 25
8. Caudal Skeleton of Bermuda Shallow Water Fishes. V. Order
Percomorphi: Carangidae. By Gloria Hollister. (Text- figures 1-20) 31
9. Description of an Egg of the Long-tailed Bird of Paradise. By
Lee S. Crandall. (Plate I) 47
10. On the Uterine Young of Dasyatis sabinus (Le Sueur) and Dasyatis
hastatus (De Kay). By C. M. Breder, Jr., & Louis A. Krumholz. (Text-figures 1 & 2) 49
11. Additional Social and Physiological Aspects of Respiratory
Behavior in Small Tarpon. By Arthur Shlaifer 55
12. Notes on Mexican Snakes of the Genus Trimeresurus. By Hobart
M. Smith 61
ZOOLOGICA
SCIENTIFIC CONTRIBUTIONS
OF THE
NEW YORK ZOOLOGICAL SOCIETY
1.
A New Crayfish from San Luis Potosi, Mexico.1 (Decapoda, Astacidae).
Horton H. Hobbs, Jr.
(Text-figure 1).
The new crayfish here described was taken by the New York Aquarium Cave Expedition to La Cueva Chica, a limestone cave in the State of San Luis Potosi, Mexico. An interesting ac- count of this cave was published by Mr. William Bridges in the Bulletin of the New York Zo- ological Society (Vol. XLIII, No. 3) in June, 1940. In this paper Mr. Bridges mentions the occurrence of crayfish in the cave, and at my request Dr. Charles M. Breder, Jr., of the New York Aquarium, and Mr. Marshall B. Bishop, of the Peabody Museum, have kindly lent me the 34 crayfish taken from the cave, and given me permission to describe them. Upon ex- amining this series I find that while they are closely allied to one of the most common species in the United States, they are distinct.
During December, 1939, an expedition from the Department of Biology of the University of Florida collected in the states of Nuevo Leon and Tamaulipas, Mexico. A fine series of an apparently new subspecies of Cambarus bland- ingii was taken one mile north of Villa Juarez, Tamaulipas, but was not described since the collection contained no first form males.
After having compared specimens of bland- ingii acutus from the southern United States with the Cueva Chica and Tamaulipas bland- ingii, I find that the specimens from Tamau- lipas are intermediate between these two, and that the Cueva Chica material represents a new race of blandingii.
Cambarus blandingii cuevachicae,
new subspecies.
Diagnosis. Cambarus blandingii cuevachicae is a member of the subgenus Ortmannicus (i. e.,
the first pleopod of the first form male termi- nates in four distinct parts, and hooks are present on the ischiopodites of the third and fourth pereiopods). Rostrum broad with small lateral teeth. Areola practically obliterated (hardly broad enough to bear a single row of punctations). Carapace strongly granulate ex- cept along median dorsal surface. First pleopod of first form male similar to that of C. blandingii acutus. (See Text-fig. 1, B and D).
Holotypic Male (Form I). Body subovate; compressed laterally. Abdomen narrower than thorax (1.54-1.91 cm. in widest parts, respec- tively).
Width of carapace greater than depth in re- gion of caudodorsal margin of cervical groove. Greatest width of carapace about midway be- tween caudodorsal margin of cervical groove and caudal margin of cephalothorax.
Areola almost obliterated in middle (hardly broad enough to bear a single row of puncta- tions) ; cephalic section of carapace about 1.7 times as long as areola (length of areola 35.2% of entire length of carapace) .
Upper surface of rostrum deeply excavate; margins slightly convex distad of base, taper- ing and forming minute tubercles at base of acumen. Acumen short and broad, extending to base of distal segment of peduncle of anten- nule. Upper surface punctate; lateral margins with setiferous punctations almost to tip of apex. Subrostral ridge not evident in dorsal view. Postorbital ridges terminate cephalad in small tubercles, not spiniform. Suborbital angle absent. Branchiostegal spines present as large acute tubercles.
•A contribution from the Department of Biology, Uni- versity of Florida, Gainesville, Florida.
1
2 Zoologica: New York Zoological Society [XX vl: 1
Surface of carapace strongly granulate except on dorsomedian surface of cephalic region; here, with setiferous punctations; one larger acute tubercle on either side in place of lateral spine, which is flanked by two or three slightly smaller ones.
Abdomen slightly shorter than carapace (3.6- 3.79 cm.).
Anterior section of telson with one spine in each posterolateral corner.
Epistome broader than long ; subminaret shaped ; margins not raised ; faveolus present at base; small obtuse tubercle on median cephalic border.
Eyes well developed.
Antennules of the usual form with a well devel- oped spine on ventral surface of basal segment.
Antennae reaching to caudal margin of telson. Antennal scale broad (broadest in middle) with a moderately well developed spine on outer dis- tal margin, reaching to distal segment oi peduncle of antennule.
First right pereiopod long and relatively slender. Hand entirely tuberculate. A single row of eight strong tubercles along inner margin of palm subtended dorsad by two weaker rows and a few scattered tubercles. Very weak ridge present on upper surface of immovable finger. Another weak ridge present on outer distal mar- gin of same finger.
Movable finger of right chela with minute tu- bercles along distal half of inner margin (crowded on distal third) . Lateral margin convex laterad ; two distinct rows of tubercles present on lateral margin along proximal two-thirds; an upper row of 24, arising near base of finger, and a lower row of 17 tubercles originating at base of distal three-fourtlis. A few scattered tubercles pres- ent on all surfaces near base of finger. Proximal two-fifths of outer margin with five tubercles. Distal upper, lower, and mesial surfaces setose punctate.
Immovable finger of right chela with minute denticles on distal two-thirds (crowded on distal third). Mesial margin concave laterad; two distinct rows of tubercles on mesial margin: the upper row with 20 tubercles along the proximal two-thirds (the fifth is decidedly larger and more conspicuous than the others) and the lower row of 13 along the proximal three- fourths (the seventh is decidedly the largest of this row). When the lingers are brought to- gether the large tubercle on the upper side of finger lies over the movable finger and the large one on the lower row extends beneath it.
Carpus longer than wide, much shorter than inner margin of palm of chela; shallow irregular furrow above. Mesial and upper mesial sur- faces tuberculate ; four large spike-like tubercles on mesial distal half; upper lateral, lateral, and ventral surfaces with setiferous punctations.
Merus with dorsal, ventral, distal mesial, and distal lateral surfaces tuberculate; proximo-
mesial and proximolateral surfaces with a few scattered punctations. Fourteen tubercles in a row on upper margin. Lower mesial margin with a row of 19 tubercles, and lower lateral margin with a row of 15 tubercles.
Hooks on ischiopodites of third and fourth pereiopods. Both hooks are slender and simple.
Coxopodite of fourth pereiopod with a large knob-like protuberance on caudomesial margin.
First pleopod extending almost to coxopodite of second pereiopod when the abdomen is flexed. Tip terminating in four distinct parts. The mesial process is subspiculiform and is directed distad and laterad; is exceeded by the other processes distad. The cephalic process is corne- ous and blade-like, somewhat rounded distad, and extends distad of the other processes; it partially overhangs the central projection. The caudal process, the least conspicuous of the four distinct terminals, lies along the caudo-lateral margin of the central projection and extends barely distad of the mesial process. This (the caudal) process is corneous, and its tip is acute. The central projection is the largest of the terminal elements; it is corneous, concave mesiad and somewhat twisted. This projection is made up of two parts, the centro-cephalic which arises just cephalad of the caudal proc- ess on the lateral surface, and the centro-caudal which is somewhat larger and forms the mesial face of the central projection. These two proc- esses are fused along an oblique line visible in lateral and caudo-lateral views only. On the lateral surface of the appendage a conspicuous knob bearing long setae arises at the base of the cephalic process.
Male Paratype (Form II). Differs from the male holotype in the following respects: Height of carapace greater than width (1.50-1.31 cm.). Postorbital ridges terminate cephalad in small acute tubercles. Branchiostegal spines moder- ately strong. Antennae reach anterior section of telson. Chelae smaller with less well defined tubercles, double row present on lateral margin of movable finger only. First pleopod termi- nating in four distinct parts; none corneous nor as sharply defined as in the first form male. (See Text-fig. 1, F and M). Hooks on ischio- podites of third and fourth pereiopods much reduced.
Female Allotype. Differs in the following points from the first form male, holotype: Width of carapace slightly less than depth. Right subrostral ridge barely evident just caudad of base of acumen. Branchiostegal spines moderately strong. Lengths of abdomen and carapace subequal. Anterior section of telson with two spines in right posterolateral corner and none in the left (broken). Epistome slightly broader and shorter than in male. Antennae reaching fifth abdominal segment. Chelae smaller and tubercle count differing — only one row of tubercles on each opposing margin.
3
1941]
Hobbs: A New Cray fish from San Luis Potosi, Mexico
Text-figure 1.
Cambarus blandingii cuevachicae, new subspecies. Pubescence has been removed from all structures illustrated. Figures not otherwise indicated are of C. blandingii cuevachicae. A, mesial view of first pleopod of C. blandingii acutus from Louisiana; B, mesial view of first pleopod of holotype; C, right chela of holotype; D, lateral view of first pleopod of holotype; E, lateral view of first pleopod of C. blandingii acutus from Louisiana; F, mesial view of first pleopod of male, form II; G, annulus ventralis of allotype; H, antennal scale of male paratype ; I, epistome of male paratype; J, ischiopodites of third and fourth pereiopods of first form male paratype; K, lateral view of carapace of holotype; L» dorsal view of carapace of holotype; M, lateral view of first pleopod of male, form II,
Zoologica: New York Zoological Society
Annulus ventralis subovate, elongate along transverse axis. Fossa projects beneath median dextral wall; sinus curving sinistrad slightly sinistrad of midventral line where it turns caudad to cut the caudal margin of the annulus. A shallow longitudinal furrow is present sinis- trad of the midventral line across the face of the annulus. Sternum just cephalad of an- nulus bearing a low tubercle on either side of the midventral line. Sternum just caudad of annulus modified into a low flat semioval struc- ture.
Measurements. Holotype: carapace, height 1.71, width 1.86, length 3.79 cm.; areola, width .02, length 1.38 cm.; rostrum, width at base 1.59, length 1.89 cm.; abdomen, length 3.6 cm.; right chela, length of inner margin of palm 1.42, width of palm 1.14, length of outer margin of hand 4.23, length of movable finger 2.53 cm. Female Allotype: carapace, height 1.87, width 1.85, length 3.83 cm.; areola, width .07, length 1.36 cm.; rostrum, width at base .64, length .89 cm.; abdomen, length 3.72 cm.; right chela, length of inner margin of palm .92, width of palm 1.00, length of outer margin of hand 2.86, length of movable finger 1.85 cm.
Type Locality. La Cueva Chica, a limestone cave, about one mile northeast of Pujal, San Luis Potosi, Mexico. These specimens were collected above the first waterfall. “Tumbled rocks alternated with shallow, narrow puddles. The going was difficult, but in the second puddle we forgot all about that, for Bishop spotted another crayfish. This time there was no es- cape, for the pool was scarcely a yard wide and twice as long. A couple of grabs and he had the creature.
[XXVI: 1
“It was not blind. Lighter in color than the normal crayfish of the outside waters, it was fully eyed and of the common local species. That was a disappointment, but it went into the pickling jar anyway.”2 The temperature of the water was 80° F.
The male holotype and female allotype and a second form male paratype are deposited in the United States National Museum. Of the paratypes, a male, form I, one male, form II, and a female are in my personal collection; one male, form I, seven males, form II, ten females, four immature males, and six immature females are in the Peabody Museum, New Haven, Con- necticut.
Relationships. Cambarus blandingii cueva- chicae is most closely allied to C. blandingii acutus. Specimens collected one mile north of Villa Juarez, Tamaulipas, Mexico, seem to be somewhat intermediate between these two, par- ticularly in respect to the width of the areola.
Remarks. I have been unable to discover any peculiarities in this race that seem to be associated with cave life. Bridges has pointed out that these specimens were of lighter color than the “normal crayfish of the outside water.” I have seen only preserved specimens so I can- not attest this observation.
On the hairy parts of the ventral surface of these crayfish were found numerous ostracods, Entocythere cambaria Marshall, and many branchiobdellid worms, Cambarincola macro- donta Ellis.3
2 Bull. N. Y. Zool. Soc. 43 (3): 84-85. May-June, 1940.
3 Dr. Clarence R. Goodnight kindly identified this bran- chiobdellid for me.
1941]
LaMonte: A New Corydoras from Brazil
5
2.
A New Corydoras from Brazil.
F. R. LaMonte
American Museum of Natural History.
Through the courtesy of the New York Aquari- um, we have secured three living specimens (approximately 15 mm.-18 mm. standard length), and seven preserved specimens (13 mm.-19 mm. standard), of a Brazilian Corydoras apparently hitherto undescribed.
These fishes formed part of a collection brought to New York by Mr. Auguste Rabaut, and col- lected by him toward the end of December, 1940, in a tributary of the Amazon. The collector never heard a name given the stream, but he reached it after seven days by river boat west from Manaos, and four more days’ journey north toward the Colombian border. The country was flooded swamp, with heavy vegetation. Mr. Rabaut reports that the water was extremely acid.
The specimens appear to represent two color patterns of the same species, the change in pattern probably occurring with growth. Each pattern, in certain lights, shows traces of the other. Of the three living fishes, the two larger are the “striped pattern;” of the preserved speci- mens, six are the “half and half” pattern, and the 19 mm. specimen is striped.
Corydoras rabauti, new species.
Description of Type. Number 15644, American Museum of Natural History, collected Decem- ber, 1940, in a tributary of the Amazon River, by A. Rabaut.
Differences in body proportions of the 19 mm. striped specimen are noted in parentheses.
Length to base of caudal, 15 mm. A rather chunky fish, with a short, rounded snout; the bony interorbital contained twice in the snout. There is no black hastate spot at the base of caudal, and the width of the naked area on the breast between the coracoids is equal to the diameter of the eye. The suborbital does not cover the entire cheek. The coracoids do not completely surround the pectoral bases on the surface of the body. The dorsal does not reach the adipose when laid back. The depth of the suborbital is equal to the diameter of the eye; the dorsal spine equal to the length of the snout. The flesh of the abdomen is smooth, without platelets.
Snout, 2.1 in the head, its profile convex, sloping gently; interorbital, 2 (1.8); eye, 3.1. Body depth in standard length, 3 (2.7); width, 3.4 (3.1); head, 2.7 (3); snout to origin of dorsal, 1.8(2). Depth of caudal peduncle in body depth, 1.4. Lateral scutes spinous, 18-20/17-20 (20/21). Lateral line pores are visible on the first two or three scutes only. The abdomen is not granular and there are no platelets.
Fontanel elongate, oval, reaching two-thirds the way to the anterior margin of eye and, pos- teriorly, to the supra-occipital process. Occipital process very narrowly triangular, not reaching azygous predorsal scute. Rictal barbels just reaching the gill-opening.
Dorsal I, 8; the spine 1.8 (1.5) in the head. The fin is rounded, the first few rays longer than the spine. Distance of the dorsal fin from the adipose, 1.3 in the dorsal base. Anal I, 6, reach- ing past origin of caudal. Pectoral passing origin of ventrals to about midway in their length; ventrals barely reaching anal. Caudal widely forked, tip of lower lobe slightly rounded.
Color in Life. Head region to short distance in front of dorsal, pinkish-orange. A dull, dark blue streak along anterior margin of eye socket, a short, very narrowly triangular metallic blue streak along posterior margin of pre-opercle. All fins except caudal, which is hyaline, are light orange, the dorsals and ventrals darkest. An ink-blue area, very slightly lighter ventrally, occupies the posterior two-thirds of the body, extending, with a concave anterior marginal outline, from in front of the dorsal origin to in front of the ventrals, entirely around the body, and back to the caudal base. On the caudal peduncle, the dark blue area becomes a short, thin line, margined by two square patches of metallic light blue. The eye is blue. In pre- servative, the lighter fins are hyaline; the dorsal and ventrals brown; the pinkish-orange body areas are faintly pink, buff or dirty light brown according to the original intensity of color; the lighter blue areas disappear as do the metallic patches; the ink-blue areas are darker and more dense.
In the 19 mm. striped pattern fish (A. M. N. H. Number 15645), the ink-blue area is confined
6
[XXVI: 2
Zoologica: New York Zoological Society
chiefly to a band, curving upward from the upper half of the caudal peduncle, following the midline of the body, but above it, and rising to a short distance in front of the dorsal origin. There are traces of bluish below this stripe on the entire posterior half of the body. The rest of the body is pinkish-orange, darkest on the head. The metallic light blue patches are as in the other fish. There is a trace of bluish on the middle rays of the caudal, not extending to the margin.
In preservative, the body of this fish is creamy, slightly darker on the head, and the ink-blue areas are darker than in life.
The species is very near eques (Steindachner, 1877, Sitz. K. Akad. Wien, volume 74, Abt. 1, p. 140. fig.), from which it differs in: a wider interorbital; a wider naked area on breast; a narrower suborbital which does not cover the entire cheek; a larger eye; longer barbels, and an apparently different color pattern.
1941]
Crandall: Notes on Plumage Changes in the Bald Eagle
7
3.
Notes on Plumage Changes in the Bald Eagle.
Lee S. Crandall
Curator of Birds, New York Zoological Park.
(Plates I-IV).
In August of 1930 a young Southern Bald Eagle ( Haliseetus leucocephalus leucocephalus (Linnaeus)), just out of the nest and barely able to fly, was captured on Little St. Simon’s Island, Georgia, by Philip Berolzheimer, of New York. In December of the same year, the young bird was brought north by Albert C. Benninger, of Brooklyn. It was kept in Forest Park, Queens, New York City, until June, 1931, when it was lent to the Girl Scout camp at Iona Island, Rock- land County, New York. On September 2, 1931, the bird was presented to the New York Zoo- logical Park and became the subject of the fol- lowing notes.
In past years, we had made several attempts to check the progressive plumages of young Bald Eagles but always some catastrophe over- took the bird before the investigation had gone very far. Consequently, on the arrival of this specimen, no notes were made. However, in the autumn of 1933, we were able to plan indoor winter accommodation for the Bald Eagles and were so confident that greater longevity could be obtained that notes on our young individual were made. On October 10, 1933, the bird being three years old and in its fourth year, the body plumage was blackish-brown in general, the breast and lower parts much mixed with white. Forehead and throat were streaked with white, and the tail (Fig. 1) was heavily blotched with gray but with no pure white. The iris was dark brown and the beak greenish-black.
On January 29, 1934, it was noted that the white streaks on the forehead had spread over the entire crown. The throat had become nearly clear white and a band of white extended to the nape. Between this band and the mottled area of the crown, was a parallel dark band, extending from the lores to the nape and passing through the eyes. During the following summer, this pattern was entirely lost. On September 2, 1934, the head, neck and throat were grayish-white, clearest on the throat but elsewhere blotched with blackish-brown, more heavily on the hind neck. The tail (Fig. 2) was extensively blotched with gray but still without clear white. The iris was light brown and the beak had become light
olive, with a hint of yellow. The voice, too, was changing, for while the bird still began his call with the harsh notes of immaturity, he ended with the clear challenge of the adult.
It was during the autumn of 1935, when the bird was five years old and in its sixth year, that it assumed what might be considered its first adult plumage. On November 1 of that year, the head and neck were recorded as pure white. The tail (Fig. 3), also, was now predominately white, although still heavily blotched with blackish-brown. The iris had acquired the pale yellowish-white of the adult and the bill, too, had become clear, pale yellow. The harsh notes had disappeared from the voice, which was now entirely clear.
The tail grown during the summer of 1936 (Fig. 4) was more clearly white but still showed a considerable flecking of blackish-brown, par- ticularly on the shafts. On November 1, 1936, it was noted that while upper and lower tail coverts were mainly white, both were heavily stippled with brown.
In November of 1937, the upper and lower tail coverts were recorded as entirely white. The tail of this year (Fig 5) showed a considerable reduction in the extent of dark stippling, though this was still present.
In 1938 (Fig. 6), 1939 (Fig. 7) and 1940 (Fig. 8), the markings on the rectrices became progressively reduced. But it was not until 1940, when the bird was ten years old and in its eleventh year, that all stippling disappeared from the vanes. Even then, as may be seen in the photograph of the tail in situ (Fig. 8), faint dark markings were still present on the shafts of some feathers.
It seems probable that there may be a con- siderable individual variation in the extent of dark markings on the shafts of the rectrices. A Bald Eagle received at the Zoological Park on March 1, 1927, had the head and tail “white.” Examination of this bird’s tail, after its death on June 17, 1940, when it must have been at least eighteen years old, showed heavy streaking of the shafts.
[XXVI: 3
S Zoologica: New York Zoological Society
Examination of the dates on which feathers were cast seems to indicate no definite procedure, except that in the last four years the outer pair dropped first and simultaneously or almost so. The earliest date for the casting of the first rectrice was April 19 (1934); the latest, June 21 (1934 and 1936). The earliest date for the casting of the last rectrice was July 30 (1934); the latest, September 25 (1938). Dates assigned to the mounted feathers indicate the time at which they were cast; in each case, they were grown in the previous year. Fig. 8 shows the tail of the living bird on December 12, 1940. The tail was grown in 1940.
Summary.
A Southern Bald Eagle ( Haliseetus leuco- ccphalus leucocephalus (Linnaeus)), hatched in
1930, was kept in the New York Zoological Park. In the autumn of 1935, when the bird was five years old and in its sixth year, the head and neck became pure white and the tail nearly so. It was not until 1940, when the bird was ten years old and in its eleventh year, that blackish stippling disappeared from the vanes of the rectrices.
Acknowledgement.
The dating and mounting of the feathers shown in the accompanying photographs were done by Herbert D. Atkin, who was a Keeper in the Department of Birds of the New York Zoological Park from 1905 to 1940, when he retired on pension. His painstaking cooperation made possible their presentation here.
EXPLANATION OF THE PLATES.
Plate I.
Fig. 1. Haliceetus l. leucocephalus. 1933 tail feathers (bird 3 years old; in 4th year) molted in 1934.
Fig. 2. 1934 tail feathers (bird 4 years old; in 5th year) molted in 1935.
Plate II.
Fig. 3. 1935 tail feathers (bird 5 years old; in 6th year) molted in 1936.
Fig. 4. 1936 tail feathers (bird 6 years old; in 7th year) molted in 1937.
Plate III.
Fig. 5. 1937 tail feathers (bird 7 years old; in 8th year) molted in 1938.
Fig. 6. 1938 tail feathers (bird 8 years old; in 9th year) molted in 1939.
Plate IV.
Fig. 7. 1939 tail feathers (bird 9 years old; in 10th year) molted in 1940.
Fig. 8. Tail feathers of the living bird (10 years old; in 11th year) photographed in situ on December 12, 1940.
CRANDALL
PLATE I
FIG. 1.
FIG. 2.
NOTES ON PLUMAGE CHANGES IN THE BALD EAGLE
CRANDALL.
PLATE I I.
FIG. 3.
FIG. 4.
NOTES ON PLUMAGE CHANGES IN THE BALD EAGLE.
CRANDALL.
PLATE I I I
FIG. 5.
NOTES ON PLUMAGE CHANGES IN THE BALD EAGLE.
CRANDALL
PLATE IV.
1 )
Dald
AGLE.
AIL
EATHERS
Dec. /Z,/?AO.
FIG. 8.
NOTES ON PLUMAGE CHANGES IN THE BALD EAGLE.
1941]
Beebe: External Characters af Six Embryo Nurse Sharks
9
4.
External Characters of Six Embryo Nurse Sharks, Ginglymostoma cirratum (Gmelin).1
William Beebe
(Plates I & 11; Text-figures 1-4).
Six embryo nurse sharks, Ginglymostoma cirratum (Gmelin), taken from a single female, have been kindly loaned to me for the study of external characters, by Commodore William K. Vanderbilt. They are borrowed from his marine museum at Huntington, Long Island, and were obtained from Mr. Louis L. Mowbray. The parent was said to be about five feet in length, and was caught in Bermuda. It was not possible to stain or section the specimens, as I agreed to return the embryos in their present condition.
The material consists of six embryos which I have designated as A to F. They are nicely graduated as to size and degree of development, and in total length measure from 73 to 152 mm. They are free, in the sense of being without shells or egg-cases, but each is attached by a short, twisted, umbilical-like extent of tissue with a large, rounded or oval mass of yolk.
In his recent monograph on Chlamydoselachus (Bashford Dean Memorial Volume Archaic Fishes, Article VII, American Museum, N. Y.), Dr. E. W. Gudger writes, “The tropical, shallow- water nurse shark, Ginglymostoma cirratum carries in each greatly dilated uterus as many as 21 huge, thick-shelled eggs.” As regards the subsequent history of these uterine eggs, Gudger on strong circumstantial evidence believes that this shark is ovoviviparous, and that when the young are pretty well developed, they break out of their shells, and these latter are cast out while the embryos are retained in the uteri during further development. A photograph of one of the unbroken egg-cases, 140 mm. long, is shown on page 560 of the Memorial Volume.
The total lengths of the six embryos under consideration are as follows: Embryo A, 73 mm.; B, 104; C, 107; D, 125; E, 138, and F, 152 mm. The relationship by weight of embryo to yolk is from 5.7% to 33%.
In embryo A the fin-folds are still sufficiently in evidence to confuse any fin base measure- ments. The first dorsal is joined to the second
1 Contribution No. 612, Department of Tropical Re- search, New York Zoological Society.
Contribution from Bermuda Biological Station for Re- search, Inc.
dorsal, and this to the caudal, by the continuation of the fin in a groove beneath the surface profile of the body. The same is true of the anal which extends forward in a subdermal groove to the vertical of the pel vies. The translucent dorsal fins in this smallest embryo show thirteen in- cipient rays in the first, and ten in the second.
External gills are present in all but embryo F, the largest. There is a gradual absorption in length of these filaments in the first five speci-
Embryo A, length 73 mm. Side view with yolk sac (X%). Dorsal view of head showing external gill filaments from spiracle and gill-slits. (X6).
10
Zoologica: New York Zoological Society
[XXVI: 4
mens. This is evident in the relationship per- centage between gill filaments and total lengths, 20%, 9.6%, 8%, 4.5%, and 3%. The smallest embryo shows the interesting condition of four external gill filaments projecting from the right spiracle, the longest of which measures 1.7 mm. in length. None are visible in the left spiracle.
In the same smallest nurse shark embryo the anterior or first gill-slit shows twenty-six long filaments and a cluster of short ones at the top of the slit. A progressively larger number spring from the next three slits, while the fifth, which is directly below the fourth, has only four filaments, these, however, being of greater length than any of the rest. This general relationship holds good for the larger embryos.
The climax of numerical development of ex- ternal gill filaments occurs in D, the 125 mm. individual. The next larger, with a total length of 138 mm., has lost all the filaments from the left first and second slits, although they are present on the right side. In E, of 138 mm., this asymmetry is reversed, the right anterior slits being free. The filaments are absorbed from be- low upward, the last to disappear being close to the dorsal ends of the slits. Those from the fourth and fifth slits are the final ones to vanish.
F, of 152 mm. length, shows no external evi- dences of filaments. In the two youngest em- bryos the fifth slit is directly beneath the fourth, but from here on to the adult shark, it is slightly behind the fourth.
As to color and pattern, the 73 mm. embryo is unspotted, as are full-grown sharks. Spots first appear, although weak and sparse, in the 104 mm. individual, and increase in strength and number up at least to embryos of 152 mm. length. In 300 mm., free-swimming nurse sharks the spots are small or obscured by the general dark pigmen- tation. A 385 mm. specimen taken on the Zaca expedition, is immaculate.
Detailed examination shows that the pattern of spots can be quite asymmetrical (specimen C, with seven spots on the right side of the body, and fifteen on the left side); or symmetrical (specimens C, E and F, with numerous transverse bands on the head and body), or somewhat irregular (specimen G). Coppery color is ap- parent in the irides of the 152 mm. individual.
The smallest and largest of seven specimens (including the six embryos, and a 385 mm. free- swimming young shark), are females. Claspers are evident in all the rest. In the 104 mm. embryo they are 4.5 mm. long, wholly attached
1941]
Beebe: External Characters of Six Embryo Nurse Sharks
11
to the inner edge of the pelvic fins, and extending to within 1 mm. of the posterior rim of these fins. There is a gradual increase in size until in the 385 mm. shark the claspers are 13 mm. long, 9 mm. below the posterior fin border, and free for 6 mm. of their length.
As the cirri or tentacles develop, their tips curve around and down, into the corners of the mouth, inside the lateral flap. This condition also holds in the young, free-swimming sharks, the tentacles being thus partly hidden and pro- tected when not in use.
In the course of embryonic development of Ginglymostoma from an embryo of 73 mm. to a full-grown shark of 2,090 mm. total length, we find there are six characters showing a percentage of increase relative to the total length, and seven- teen which are on the minus side. The body depth is somewhat greater in the adult, the
general flattening being especially noticeable in unborn individuals. The head, both in length and width, snout, preoral, interorbital and in- ternarial, all show relative reduction in the adult, as much as 3.7% in head length, and 4.4% in the snout. The mouth width, on the contrary, is slightly greater.
The eye, length of tentacle and of spiracle are markedly less in the full grown shark. The heights of the three median fins, first and second dorsals and anal enlarge steadily from early em- bryo onwards, even reaching a 4.6% increase. The pectorals exceed these, registering width and length increases of 5.7% and 7.6%.
There is considerable reduction in antero- posterior measurements from snout to first and second dorsals, as well as to pectorals, pelvics and anal fins. The bases of all the median fins are relatively less in the adult, partly because of the slow disappearance of the fin-fold.
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[XXVI: 4
Text-figure 4.
Embryo F, length 152 mm. Right and left side views with yolk sac.
We may safely deduce that throughout the life of this shark there is an increasing need for large pectorals and a general flattening of the body in relation to the bottom-living habits, while correlated with this is a reduction of the head, with its tentacles, eyes and spiracles, and a relative shortening of the whole body. In fact, Ginglymostoma tends in development rather to- ward a bottom-living, ray-like type, than to a mid-water, shark-like organism.
Developmental characters showing a plus per- centage in relation to total length are these : depth
2%, pectoral length 7.6%, pectoral width 5.7%, first dorsal height 4.6%, second dorsal height 2.3%, anal height 1.3% and mouth width 1%. Characters showing minus percentage in develop- ment are head 3.7%, head width 1.7%, snout 4.4%, interorbital 4.6%, eye 2%, snout to first dorsal 4.6%, snout to second dorsal 3%, snout to pectoral 4.6%, snout to pelvics 5.2%, snout to anal 3.6%, first dorsal base 2.1%, second dorsal base 2.3%, anal base 3.1%, snout to mouth 2.6%, tentacle length 2.5%, internarial 1.3% and spiracle length .5%.
EXPLANATION OF THE PLATES.
Plate I.
Fig. 1. Embryo B, length 101 mm. Shark, showing external gill filaments and yolk sac.
Fig. 2. Embryo D, length 125 mm. Shark, showing right side and yolk sac.
Plate II.
Fig. 3. Embryo F, length 152 mm. Dorsal and right side views and yolk sac.
Fig. 4. Embryo F, length 152 mm. Ventral view and yolk sac.
BEEBE
PLATE I
FIG 1.
FIG 2
EXTERNAL CHARACTERS OF SIX EMBRYO NURSE SHARKS, GINGLYMOSTOMA CIRRATUM (GMELIN).
BEEBE
PLATE I I.
FIG. 3.
FIG. 4
EXTERNAL CHARACTERS OF SIX EMBRYO NURSE SHARKS. GINGLYMOSTOMA CIRRATUM (GMELIN).
1941]
Smith: A Papillomatous Disease of the Gallbladder
13
5.
A Papillomatous Disease of the Gallbladder Associated with Infection by Flukes, Occurring in the Marine Turtle, Chelonia my das (Linnaeus).1
G. M. Smith
Department of Anatomy, Yale School of Medicine, and the New York Aquarium
&
C. W. Coates & R. F. Nigrelli
New York Aquarium
(Plates I— IV ; Text-figure 1).
In two earlier publications attention was called to certain cutaneous tumors occurring in the turtle Chelonia mydas (Linnaeus) (Smith & Coates, 1938, 1939). These growths, fibro- epithelial in character, are found distributed on the neck and in the axillary, inguinal, eyelid, conjunctival and corneal regions. As a rule the tumors have the morphological characteristics of benign growths ; rarely does the structure suggest a malignant change. In the majority of such tumors ova of a blood fluke can be demonstrated on microscopical study, giving rise to the hy- pothesis that blood flukes or ova may act as causative factors in the production of these lesions. In earlier studies ova occurring in cu- taneous tumors were identified as those coming from Hapalotrema constrictum (Leared). Recent studies of a number of these worms (Nigrelli, 1940), however, indicate that this blood fluke is the same as Distomum constrictum of Leared (1862) and the form described by Price (1934) as Learedius learedius. The form described as Ha- palotrema constrictum (Leared) Looss, 1899 ( = Mesogonimus constrictum Monticelli, 1896) is now designated as Hapalotrema mistroides (Monticelli). This form is also a blood fluke but found in an- other species of marine turtle Caretta caretta (Lin- naeus) (= Thalassochelys caretta (Linnaeus)). It must lie pointed out here, however, that the original identification was tentative and based on the shape and size of the eggs, which are strikingly similar. Relationships and identifications of worms have been based on egg characteristics by various taxonomists.
Further studies of lesions in turtles as a result of fluke infections, carried on during the past year, have revealed a new form of papillomatous disease of the gallbladder of Chelonia mydas
1 Aided by a grant from the Marine Cancer Fund of Yale University School of Medicine.
which may be the result of a fluke infection of this organ.
A brief description of the gallbladder lesions and of the fluke itself follows.
Infected gallbladders show a wide range of lesions, depending doubtless upon the intensity and duration of the infection and the suscepti- bility of the tissues of the host. Any part of the fundus of the gallbladder may show thickened papillomatous change in solitary patches (Plate I, Fig. 1; Plate II, Fig. 4) or in confluent irregular masses (Plate I, Fig. 2). A papillomatous hyper- plasia of the mucous membrane near the cystic duct’s entrance into the gallbladder may be the most conspicuous lesion, the result of infection by trematodes (Plate II, Figs. 4, 5,6). Inconsequence, the cystic end of the gallbladder may appear greatly thickened and encroaching on the lumen of the gallbladder (Plate IV, Fig. 12) almost to the point of producing a stenosis or obstruction. At times the entire wall of the gallbladder partici- pates in the lesion. In these circumstances the epithelium is thrown up into papillomatous folds (Plate III, Figs. 7, 8), the muscularis shows in- creased amounts of connective tissue and lymph- oid cell infiltration and the subserosa may be oedematous, thickened, and contain a large number of dilated capillaries both vascular and lymphatic. All sorts of irregularly dilated glands are formed in the hyperplastic epithelium. Often glands penetrate down into the submucosa. However, malignant invasive changes have not been noted to date in approximately one hundred gallbladders examined which have shown the effects of fluke infection. Malignant change might readily be expected as a result of these chronic hyperplastic changes. In order to de- termine whether or not the papillomatous lesions do become malignant it will be necessary to have
14
[XXVI: 5
Zoological New York Zoological Society
access to more extensive material than is avail- able at the present time.
The majority of the flukes lie free in the dark green, thickened, often inspissated bile of the infected gallbladder. Flukes often are attached to the papillomatous parts of the mucous mem- brane (Plate IV, Fig. 11). The parasites may lie partly buried in the mucosa (Plate I, Figs. 1, 2). There can be little doubt that the presence of flukes at the site of characteristic lesions of the mucous membrane indicates that the underlying- cause of the disease arises in mechanical or chemical factors related to the activities of the infecting flukes. Ova surrounded by epithelioid or even giant cells may be found in the mucous membrane or other parts of the walls of the gall- bladder (Plate III, Fig. 9). Mucous production is abundant (Plate III, Fig. 10).
The parasites from the gallbladder of Chelonia mydas have been identified as Rhytidodoides similis Price, 1939. A related species R. intesti- nalis was described in the same paper. According to Price, the identifications of “Both R. intesti- nalis and R. similis are in each case based on only two specimens; consequently it is not possible to determine the amount of variation within the species.” A collection of large numbers of the gallbladder form has afforded an opportunity to make just such a study for this species, at least (Text-figure 1).
The worms are lanceolate in shape, tapering at both ends of the body and broadening consider- ably in the middle region. The posterior tip of the body can be extended into a minute “tail- like” appendage. When the flukes are examined in profile there is a characteristic hump on the dorsal side. In contracted specimens, the hump is more pronounced than in the extended forms. On the ventral surface, the acetabulum is promi- nent'and immediately anterior to this sucker may be seen the genital ridge and pore.
The flukes are transparent and stained with bile. They measure 1.2 x .42-4.4 x 1.8 mm., with an average size of 2.2 X .97 mm. for fifty specimens. Cuticula without spines, smooth in expanded worms, with minute folds in contracted specimens. Oral sucker subterminal, measuring 140.2-342 microns in diameter (average, 293.4 microns), with lateral projections. The projec- tions are prominent in the smaller individuals, less so in larger forms but are nevertheless a constant feature. Acetabulum, 170.3-385.6 microns (average, 300.7 microns), pre-equatorial. Pre-pharynx lacking; pharynx 80-179 X 50-170 microns; esophagus of variable length, depending entirely on the state of contraction and expansion of the worms. Intestinal ceca simple, extending to the posterior extremity of the body. Excretory pore subterminal, dorsal; excretory vesicle Y- shaped, branching immediately behind the pos- terior testis, with the arms extending as far anterior as the pharynx. Genital aperture median, anterior to the ventral sucker and in the region of the cecal bifurcation. Cirrus pouch elongate piriform, muscular, situated over or
slightly in front of the acetabulum, measuring 150-700 microns X 150-456 microns (average measurement 152 X 478.8 microns). Seminal vesicle and pars prostatica present. Testes in posterior third of the body, placed one behind the other or slightly oblique to the axis of the body, sometimes globular, sometimes sub-globular or ovoid in shape. Anterior testis usually smaller, measuring 102-420 microns X 250-456 microns; posterior testis 152-532 microns in diameter. In very small forms testes and vitellaria are poorly developed. Ovary globular, 91-280 microns in diameter (average, 250 microns), sub-median and pre-testicular in position. Ovarian complex, con- sisting of Mehlis’ gland, seminal receptacle, vital- line reservoir, and Laurer’s canal. Vitellaria consist of four groups of more or less elongated follicles; two small groups of follicles are in the anterior region of the body and present as two distinct masses, one on each side of the esophagus between the acetabulum and pharynx; the two larger groups extend from the acetabulum to the posterior extremity of the body. Main vitelline ducts pass medially into the ovarian complex at about the level of the posterior border of the ovary. Uterus fills the entire intercecal space between the ovary and acetabulum; metraterm present. Eggs yellowish, thick-shelled, embryo- nated, measuring on the average 36 X 72 microns.
Comment.
The histo-pathology of trematode infections among lower vertebrates is not well known. The condition reported above is in many respects not unlike liver fluke infections in mammals (see Craig & Faust, 1940).
In sheep liver fluke, Fasciola hepatica Linnaeus, larvae are ingested with contaminated vegeta- tion. Excystment takes place in the duodenum where the parasites penetrate the wall and pass into the body cavity. They continue their migration, passing through the liver capsule directly into the liver substance. The mechanical irritation produced, in the case of heavier infec- tions, results in necrosis and fibrosis of the liver. Such an infection in man may cause cystic en- largement of the ducts, adenomata of the biliary epithelium, leucocytic and eosinophilic infiltra- tion, and eventually the development of scar tissue. Often, in their wanderings through the liver substance, the worms produce abscesses, and the mechanical damage causes atrophy of the liver and the portal vessels.
Local lesions of this kind may be produced by other liver flukes such as the lancet fluke, Dicrocoelium dentriticum (Rudolphi), the cat liver fluke, Opisthorchis felineus (Rivolta), and the Chinese liver fluke, Clonorchis sinensis (Cobbold).
In dicrocoeliiasis, sheep and other herbiverous mammals become infected by eating grass and other vegetation containing encysted larvae. When eaten, such larval forms excyst in the duodenum and find their way to the biliary passages, often producing hypertrophy of the
1941]
Smith: A Papillomatous Disease of the Gallbladder
15
epithelium. Both opisthorchiasis and clonor- chiasis infections are brought about by eating fish poorly cooked, improperly cured, or raw, harboring the encysted stage.
In clonorchiasis, the larvae, following excyst- ment, make their way up the common bile duct and migrate to the distal bile capillaries. Lesions produced by such infections have been described by Faust & Khaw (1927), Hoeppli (1933) and
others. These include the proliferation of bili- ary epithelium, crypt formation in the bile duct, periepithelial fibrosis, periportal connective tissue hyperplasia and fibrous development around masses of eggs infiltrated in the liver substance.
Although the papillomatous disease of the gallbladder of Chelonia mydas is stressed in the present contribution, there are also definite re- sponses in the liver and biliary ducts of these
16
[XXVI: 5
Zoologica: New York Zoological Society
animals which will be discussed in a subsequent report.
Summary.
1. Gallbladders of the marine turtle Chelonia mydas (Linnaeus) were found heavily infected with a fluke referred to as Rhytidodoides similis Price, 1939.
2. These flukes produce certain pathological changes in the tissues of the gallbladder. The outstanding feature of these lesions is a papillo- matous hyperplasia of the mucous membrane.
3. The parasites inducing these lesions are redescribed.
References Cited.
Craig, C. F. & Faust, E. C.
1940. Clinical Parasitology. Lea and Febiger, Phila. 772 pp., 244 text-figures.
Faust, E. C. & Khaw, O. H.
1927. Studies on Clonorchis sinensis (Cobbold). Amer. Jour. Monogr. Series, (8), 339 pp.
Hoeppli, R.
1933. Histological changes in the liver of sixty- six Chinese infected with Clonorchis sinen- sis. Chinese Medical Journal, JR': 1125- 1141.
Leared, Arthur
1862. Description of a new parasite found in the heart of the edible turtle. Quart. J . Micr. Soc., London, n. s., 2: 168-170.
Looss, A.
1899. Weitere Beitrage zur Kenntnis der Trema- toden-Fauna Aegyptens zugleich Versuch einer naturlichen Gliederung des Genus Distomum Retzius. Zool. Jahrb., Jena, Abt. f. Syst., 12: 521-784.
Monticelli, F. S.
1896. Di un ematozoo della Thalassochelys caretta Linn. Internat. Monatschr. f. Anat. u. Physiol., Leipz. 13: 141-172.
Nigrelli, R. F.
1940. Observations on Trematodes of the Marine Turtle, Chelonia mydas. Anat. Rec., 78, no. 4, Supph: 178.
Price, Emmett W.
1934. New Genera and species of blood flukes from a marine turtle, with a key to the genera of the family Spirorchidae. J. Washington Acad. Sci., 24: 132-141.
1939. A new Genus and two new species of digenetic trematodes from a marine tur- tle. Proc. Helminth. Soc., Washington, 6: 24-25.
Smith, G. M. & Coates, C. W.
1938. Fibro-epithelial growths of the skin in large marine turtles, Chelonia mydas (Linnaeus). Zoologica, 23: 93-98.
1939. The occurrence of trematode ova, Hapalo- trema consirictum (Leared), in fibro- epithelial tumors of the marine turtle, Chelonia mydas (Linnaeus). Zoologica, 24: 379-382.
EXPLANATION OF THE PLATES.
Plate I.
Fig. 1. Strip of gallbladder mucous membrane showing to the right a small papilloma with several flukes attached to or partly buried in the mass.
Fig. 2. Photograph of inside of gallbladder attached to the liver. Note confluent masses of papillomatous tissue; flukes lie attached or partly buried in the growth.
Plate II.
Fig. 3. Section of normal gallbladder containing bile.
Fig. 4. Thickened, shrunken, infected gallbladder with several small papillomata near the entrance of the cystic duct.
Figs. 5-6. Small contracted gallbladders infected by fluke, Rhytidodoides similis. The great thickening of the mucosa and submucosa has occurred near the cystic duct.
Plate III.
Figs. 7-8. Irregular hyperplasia of papillomatous regions of infected gallbladders. X 35.
Fig. 9. Photo-micrograph of papillomatous region of gallbladder showing fragments of ova at points a and b. Epithelioid cells surround the small fragment at b. X 120.
Fig. 10. Masses of mucous formed at the surface of papilloma. X 100.
Plate IV.
Fig. 11. Microscopic section of trematode Rhytido- doides attached to the hyperplastic epi- thelium of the gallbladder. Section of the parasite is at the level of the ventral sucker and the cirrus sac. X 40.
Fig. 12. Photo-micrograph of the cystic end of infected gallbladder. The hyperplastic mucous membrane is thrown into countless folds which encroach upon the lumen of the gallbladder. Submucosa and muscularis are thickened. The subserosa seen in the upper part of the photograph is oedema- tous and contains numerous blood and lymphatic vessels. X 25.
SMITH
PLATE I.
|
(Ill INI III! II |
1! HI |
i mi in |
1 IITI Nil |
mi mi i |
|
2 3 |
4 |
1 i |
m ) o |
7 |
FIG. 2.
A PAPILLOMATOUS DISEASE OF THE GALLBLADDER ASSOCIATED WITH INFECTION BY FLUKES, OCCURRING IN THE MARINE TURTLE, CHELONIA
MYDAS ( LINNAEUS ) .
SMITH.
PLAT
FIG. 3. FIG. 4.
FIG. 5.
A PAPILLOMATOUS DISEASE OF THE GALLBLADDER ASSOCIATED WITH INFECTION BY FLUKES. OCCURRING IN THE MARINE TURTLE CHELONIA
MYDAS ( LINNAEUS ) .
SMITH
PLATE III
FIG. 7
FIG. 8.
FIG. 9. FIG. 1 O .
A PAPILLOMATOUS DISEASE OF THE GALLBLADDER ASSOCIATED WITH INFECTION BY FLUKES. OCCURRING IN THE MARINE TURTLE. CHELONIA
MYDAS (LINNAEUSl
SMITH
PLATE IV.
FIG. 1 1 .
FIG 12.
A PAPILLOMATOUS DISEASE OF THE GALLBLADDER ASSOCIATED WITH INFECTION BY FLUKES. OCCURRING IN THE MARINE TURTLE CHELONIA
MYDAS ( LINNAEUS) .
1941]
Treadwell: Polychaetous Annelids from Mexico
17
6.
Eastern Pacific Expeditions of the New York Zoological Society. XXIII.
Polychaetous Annelids from the West Coast of Mexico and Central America.1
Aaron L. Treadwell Department of Zoology, Vassar College
(Text -figures 1-21).
Contents.
Introduction .17
Systematic Account.
Family Amphinomidae
Hermodice carunculata Kinberg 17
Notopygos ornata Grube 18
Chloeia euglochis Ehlers 18
Eurythoe, complanata Pallas 18
Eurythoe oculata sp. nov .18
Family Polynoidae
Lepidasthenia picta Treadwell . 18
Lepidasthenia elegans sp. nov 19
Halosydna brevisetosa Kinberg 20
Family Sigalionidae
Eupholoe nuda Treadwell 20
Polyodontes californicus sp. nov 20
Family Aphroditidae
Aphrodita Linnaeus 21
Family Phyllodocidae
Phyllodoce oculata Ehlers 21
Phyllodoce groenlandica Oersted . . . ..21
Eulalia magnapupula sp. nov. '. .21
Family Tomopteridae
Tomoptcris opaca Treadwell . . 22
Family Typhloscolecidae
Travisiopsis atlantica Treadwell 22
[This is the twenty-third of a series of papers dealing with the collections of the Eastern Pacific Expeditions of the New York Zoological Society made under the direction of Dr. William Beebe. The present paper is concerned with specimens taken on the Eastern Pacific Zaca (1937-1938) Expedition, which was made possible through the generosity of Mr. Templeton Crocker. For data on localities, dates, dredges, etc., refer to Zoologica, Vol. XXIII, No. 14, pp. 287-298.]
Introduction.
The following is a taxonomic account of 30 species of polychaetous annelids collected by Dr. William Beebe on the Eastern Pacific Zaca Ex- pedition in 1937-1938. Five new species are
1 Contribution No. 613, Department of Tropical Re- search, New York Zoological Society.
Family Leodicidae
Leodice longisetis Webster .22
Leodice paloloides Moore .22
Diopalra ornata Moore 22
Hyalinoecia juvenalis Moore .22
Arabella pacifica sp. nov 23
Family Amphictenidae
Peclinaria gouldii Verrill 23
Family Opheliidae
Ammotrypane bermudiensis Treadwell 23
Family Capitellidae
Notomastus sp 23
Family Glyceridae
Hemipodus mcxicanus Chamberlin 23
Family Chlorhaemidae
Stylarioides sp 23
Family Terebellidae
Terebella gorgonae Munro 23
Terebellides stroemi Sars 23
Family Sabellidae
Sabella melanostigma Schmarda 23
Bibliography 24
included in the collection. They were collected from off Cedros Island, Lower California, on the north to Panama Bay on the south.
The catalogue numbers all refer to specimens in the collections of the Department of Tropical Research of the New York Zoological Society.
Systematic Account.
Family Amphinomidae.
Hermodice Kinberg.
Hermodice carunculata Kinberg. Hermodice carunculata Kinberg, 1857, p. 13.
Collected at Arriba Isthmus, Port Parker, Costa Rica, January 17, 1938, Cat. No. 3,882A.
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Notopygos Grube.
Notopygos ornata Grube.
Notopygos ornata Grube, 1856, p. 55.
Collected at Station 203: D-9 (Port Parker, Costa Rica, January 22, 1938, 2 fathoms), Cat. No. 381,093.
Chloeia Savigny.
Chloeia euglochis Ehlers.
Chloeia euglochis Ehlers, 1887, pp. 18-24; pi. 1, figs. 1, 2; pi. 2, figs. 1-8; pi. 3, figs 1M.
Collected at Station 195: D-9 (Port Guatulco, Mexico, December 5, 1937, in 7 fathoms), Cat. No. 37,477. Collected at Port Guatulco, Mexico, December 5, 1937, in fish trap at 7 fathoms. Color plate Z-118, Cat. No. 37,429. Station 221 : D-l (Gulf of Chiriqui, Panama, March 13, 1938, 35 fathoms), Cat. No. 38,659.
Specimen 37,477. Dorsal surface iridescent purplish-gray with a wide blackish band down the middle of each side within which are numer- ous oblique yellow streaks. On the mid-dorsal line of each segment are a pair of longitudinal, slightly oblique yellow lines. Tentacles and dor- sal cirri greenish-black; setae bright orange. Gills greenish-brown, with a central yellow band on each stem.
Eurythoe Kinberg.
Eurythoe complanata Pallas.
Eurythoe complanata Pallas, Teste McIntosh. McIntosh, 1885 (as E. pacifica Kinberg), pp. 27, 28; pi. 2, figs. 3, 4; pi. 3, fig. 3; pi. 2A, fig. 13; pi. 3A, figs 5-9.
Collected at Station 195: D-15 and D-16 (Port Guatulco, Mexico, December 6, 1937, in 1J4 fathoms), Cat. No. 37,526. Sihuatanejo, Mexico, November 24, 1937, in coral, Cat. No. 37,266. Station 196: D-18 (Tangola-Tangola Bay, Mexico, December 13, 1937, 30 fathoms), Cat. No. 37,743. Aba,jo Rocks, Port Parker, Costa Rica, January 22, 1938, tide-pool, Cat. No. 381,094.
Eurythoe oculata sp. nov.
(Text-figures 1-3).
A single specimen. The body is broken and more or less macerated near its middle so that accurate measurements are impossible but it is approximately 180 mm. long. The greatest width, 10 mm., is at about the end of the anterior third of the body length. The prostomial width is 1 mm.
The prostomium (Text-fig. 1), is ovate with its broader end anterior, and has two pairs of promi- nent eyes. The anterior tentacles are slender and reach as far as to the anterior prostomial border. The median tentacle is relatively long, is attached at the level of the posterior eyes and extends to the anterior border of the anterior ones. The
tentacles are colorless, as is the prostomium. The caruncle is very small and inconspicuous and is attached to the dorsal border of the first somite (Text-fig. 1). This prostomium has certain re- semblances to that of E. duhia Horst as redefined by Munro (1933, p. 5), but is longer in proportion to width than in his figure 1, the eyes are much more prominent and the tentacles more slender. Horst (1912, p. 37), and Munro describe the caruncle as fiexuous though this is more clearly shown in Horst’s figure than in Munro’s. In oculata it is hardly more than a rounded papilla.
The parapodial lobes are widely separated. The dorsal cirrus is prominent and lies anterior to the tuft of gills. Two dorsal aciculae with rounded ends protrude to the surface at the base of the cirrus and three similar aciculae occur in the neuropodium (Text-fig. 2). The ventral cir- rus is a rounded cone. The notosetae make up a dense tuft, are all alike, long, slender and sharp- pointed. Sometimes it is possible to see on the shafts the denticles figured by Horst ( loc . cit., pi. 10, fig. 7), but generally they seem smooth. I am uncertain what he meant by “dimples” on the shafts, and can find nothing that would answer to this description. The neurosetae (Text-fig. 3), are heavy, with apices bluntly rounded and an also bluntly rounded, subapical tooth.
The gills first appear on the third somite and when well developed consist of a tuft of 12 or more filaments arising from a common base just behind the insertion of the dorsal cirrus. A few filaments may be simple but most are at least 2-branched and some are irregularly dichoto- mously divided into as many as 6 branches.
The type was collected at the dock in Balboa, Panama, July 25, 1933. It is a female with eggs, and is No. 3,319 in the collection of the Depart- ment of Tropical Research of the New York Zoological Society.
Family Polynoidae.
Lepidasthenia Malmgren.
Lepidasthenia picta Treadwell.
Lepidasthenia picta Treadwell, 1928, pp. 456, 457; fig. 177; figs. 10-13.
A single specimen in this collection makes possible additions and corrections to the original diagnosis. The drawing (loc. cit., fig. 10), shows a dividing line between the lateral prolongation of the prostomium and the cirrophore of the tentacle. This is incorrect. The cirrophore is a prolongation of the prostomium. In the type the palps and elytra were missing. In the Zaca material the former show as stout structures shorter than the median tentacle and having acuminate tips. The anterior elytra are approxi- mately circular in outline and cover the tentacles which may be seen through them. The anterior dorsal margin of the elytron is faintly tinged with black and there is a small black spot ventral to the point of elytrophore attachment. Later elytra are more lateral in position, leaving a con-
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19
Text-figures 1-21.
1-3. Eurythoe oculata sp. nov. 1, head X 7; 2, parapodiuin X 0; 3, neuroseta X 62. 4-7 . Lepidas-
thenia elegans sp. nov. 4, head X 12; 5, parapodium X 20; 6, notoseta X 180; 7, neuroseta X 180. 8, Elytron of Eupholoe nuda Treadwell X 25. 9-12. Polyodontes calif ornicus sp. nov. 9, head X 18; 10, parapodium X 5; 11, seta X 85; 12, seta X 180. 13-17. Eulalia magnapupula sp. nov. 13,
dorsal surface of headX 10; 14, ventral surface of head X 10; 15, parapodium X 33; 16, seta X 250; 17, seta X 250. 18-21. Arabella pacijica sp. nov. 18, head X 15; 19, seta X 68; 20, maxilla X
23; 21, mandible X 23.
siderable portion of the dorsum exposed. While anterior elytra are lightly pigmented, throughout the median and posterior regions the pigmenta- tion is dense except for a colorless spot over the elytrophore, this giving an ocellated appearance to the dorsal surface. The elytra have neither marginal fringes nor surface spines. The body coloration is somewhat different from that of the type, indicating some degree of variability.
Collected at Station 203: D-9 (Port Parker, Costa Rica, January 22, 1938, in 1^2 to 4 fath- oms), Cat. No. 381,092.
Lepidasthenia elegans sp. nov.
(Text-figures 4-7).
Two specimens are in the collection, the type being incomplete. This is 25 mm. long and 10 mm. wide at the tenth somite. In the other, which is entire, the posterior region is badly pre- served and it is impossible to determine the number of somites or of the elytra. The speci- mens are assigned to this genus subject to later correction. The prostomium (Text-fig. 4), is 1 mm. in diameter, is broader than long and has a
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broad but not deep, anterior indentation into which fits the heavy cirrophore of the median tentacle. From the base of this indentation a dorsal groove runs posteriorly along the pros- tomial surface. The eyes are all near the pos- terior border, the posterior ones the smaller, nearer together and more or less covered by the margin of the first somite. The median cirro- phore is heavy, its length rather more than half that of the prostomium. The style is about as long as the prostomium up to the point where it begins to taper and it has a slender terminal filament. Cirrophores of the lateral tentacles are short and stout, their styles shaped much like those of the median but only about two-thirds as long. The ventral tentacular cirrus is similar in form to the median tentacle, the dorsal one similar to the lateral tentacle but much more slender. The palps are slender and inconspicu- ous, hardly longer than the median tentacle. The first somite, carrying the elytrophore, is twice as wide as the prostomium, later ones in- crease in width up to the sixth.
The coloration is unlike in the two specimens, the type having five or six dark transverse bands on its dorsum in each somite, while the other has two irregular ones in this locality. Except for a slight tint near the apex of the palp there is no color in the head region.
The parapodium has a much reduced notopo- dium into which a stout acicula extends, the neuropodium is much heavier and rounded at the apex, anterior and posterior lobes equal (Text- fig. 5). The dorsal cirrus is on a heavy cirrophore whose diameter is more than half that of the parapodium, its style reaching considerably be- yond the parapodium apex, slightly swollen near the end and terminating in a heavy filament. The ventral cirrus is very short, conical and has a slender tip. All but one of the notopodia examined had no setae, the exception having a single one. This was rather heavy, its apex bluntly rounded (Text-fig. 6), and it has trans- verse rows of teeth along one border, these being heavier than those in the neuropodium. There are about ten setae in the neuropodial group, these differing from one another mainly in size. They have rather heavy stalks which are swollen near the ends and then narrow to blunt points. Very small teeth, difficult to see unless the seta is in the proper position, occur along one margin of the swollen portion (Text-fig. 7).
The protruded pharynx is as long as the first seven somites. Dorsally and ventrally at its apex are marginal rows of nine papillae.
Anteriorly the elytra cover the dorsum. I am unable to say what the condition is in later somites. All elytra are circular in outline, the surface dotted with pigment spots and devoid of marginal filaments.
The specimens are recorded as commensal in a holothurian. They were collected at Station 126: D-14 (East of Cedros Island, Mexico in 45 fathoms), Cat. No. 3,773. The type is in the collection of the Department of Tropical Re- search of the New York Zoological Society.
Halosydna Kinberg.
Halosydna brevisetosa Kinberg.
Halosydna brevisetosa Kinberg, 1865, p. 85. Collected at Station 126: D-19 (S. E. of Cedros Island, Mexico, November 10, 1937, in 25 fath- oms), Cat. No. 3,794.
Family Sigalionidae.
Eupholoe McIntosh.
Eupholoe nuda Treadwell.
(Text-figure 8).
Eupholoe nuda Treadwell, 1936, pp. 53, 54; figs. 10-14.
As Eupholoe nuda I described a specimen from Bermuda in which I was uncertain whether all elytra had been lost or whether they had ever been present. The present collection contains one of this species with a full complement of elytra. They are decidedly lateral in position, leaving a considerable portion of the dorsum un- covered, and are essentially of the same form throughout the body. They, as well as the body surface, are covered with sand grains of which the largest on the elytra are those of the antero- dorsal area, some of which protrude beyond the elytral border (Text-fig. 8). The smallest of the grains are at the posterodorsal region where there are also some long marginal filaments. On the posteroventral face are two branched filaments and small ones occur on the remainder of the border except for a small part of the dorsal region where there are neither filaments nor sand grains. At this region the elytral surface is dotted with small spines.
My earlier material showed two kinds of com- pound setae ( loc . cit., figs. 13, 14), one much heavier than the other, the slender one with a subterminal tooth. The present material shows that the subterminal tooth is present on both kinds of setae but evidently is easily broken away. The setae differ, therefore, only in size.
Collected at Station 126: D-19 (S. E. of Cedros Island, Mexico, November 10, 1937, in 25 fathoms), Cat. No. 3,794.
i
Polyodontes californicus sp. nov.
(Text-figures 9-12).
The type and only specimen is a fragment, measuring 25 mm. to the region of the 20th ely- tron, and has a width of 10 mm. The prostomial diameter is about 1 mm., each half continued into an ommatophore, the base of each ommatophore being at about half way of the total prostomial- eye length, the apex of the eye being a trifle wider than the width of the stalk. There is a lens at the end. The sessile eyes are a pair of small dark spots, one on either side (Text-fig. 9). The base of the median tentacle is at the level of these sessile eyes and its stalk very slender, its apex narrowing to a filamentous tip which does not quite reach the apex of the ommatophore. At base of median tentacle is a ring of brownish pig-
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Treadwell: Polychaetous Annelids from Mexico
ment and a median caruncle-like ridge runs pos- teriorly across the dorsal prostomial surface. The lateral tentacles are similar to the median in form and size but are not visible from the dorsal sur- face, being hidden beneath the ommatophores. Each has a pigmented ring at the base and anoth- er just proximal to the filamentous tip. The palps are slender, nearly three times as long as prosto- mium and ommatophores combined and are pig- mented near the apices. The basal portion of the tentacular cirri extends as far as the base of the ommatophores, the styles slender, extending as far as the apex of the eyes, their apices abruptly ending in slender filaments. There is a band of brown pigment near the apex of the cirrophore and the dorsalmost cirrus has pigment near its apex and another pigmented mass near its base.
The protruded pharynx extends 10 mm. be- yond the prostomium and at its apex is 7 mm. wide. The dorsalmost terminal papilla of the pharynx is 4 mm. long and on either side of it a row of 7 broad, flattened papillae with acute apices. The outermost one of each row is much the smallest and in most of them is a dark spot. The ventral median papilla is short, similar to, but a little larger than, the lateral ones of which there are 6 on either side. There are two light brown fangs with a single row of teeth on either side of each pair.
The protrusion of the pharynx produces enough distortion so that it is not possible to determine exactly the position of the anterior elytra. Evi- dently the first pair covers the prostomium and is colorless except for a few widely distributed black spots. The second is much smaller than the first, the third larger than the second but still smaller than the first. These have a few dark spots. The fourth is about as large as the third and diffusely pigmented. Beginning with the fifth, a considerable area of the dorsal surface is uncovered by elytra and these assume a very characteristic coloration and form. Each is ap- proximately oval in outline, its long axis vertical and the outer end wider than the inner. Near the dorsal end is a densely pigmented band, separated by a colorless band from the elytron margin. From one-half to one-third of the ely- tron surface shows more or less pigmentation, the densest portion being the dorsal area mentioned above. The combined effect is that of two dark brown bands along the dorso-Iateral surface of the body. A very faint brownish tint, due to numerous small transverse lines, marks the dorsal surface beneath the elytra. The remainder of the body is colorless. The first pair of ventral cirri are very large, following ones successively smaller, most reaching only to end of parapodium. The dorsal cirri are nearly of the same size throughout.
A median parapodium has nearly equal an- terior and posterior setal lobes and a spoon- shaped lip underlying the neuropod (Text-fig. 10). The dorsal cirrus has a heavy cirrophore and a conical style reaching a short distance beyond the setal lobe. The ventral cirrus is much more slender, its acute tip just about reaching the end of the neuropod. There are three types of setae.
The first lie in the median portion of the row, have heavy brown shafts slightly enlarged and curved toward ends, apex obliquely truncated (Text-fig. 11). To this truncated portion is at- tached a slender terminal joint having fine hairs on its surface. Above and below these are slender setae, their apices very slender lanceolate in outline, the terminal portion covered by fine hairs. Another and larger tuft of colorless setae lies ventral to the heavy ones. These (Text-fig. 12) widen toward the ends and are curved. At the curve are toothed plates and beyond these, fine hairs cover the entire surface.
The gills are bladder-like structures on the dorsal parapodial surfaces and are most promi- nent on the elytra-bearing somites.
This species is here classed in the genus Polyodontes, because of the presence of gills. If, however, Chamberlin’s synonymy is correct (1919, p. 86), Polyodontes is preoccupied and it should be listed as Acoetes.
The type was collected at Station 182: D-4 (Chamela Bay, Mexico, November 17, 1937, in 16 fathoms), Cat. No. 37,152, and is in the col- lection of the Department of Tropical Research of the New York Zoological Society.
Family Aphroditidae.
Aphrodita Linnaeus.
Specimens of Aphrodita, all too badly pre- served to admit of species identification, were collected at Station 189: D-2 (17 miles S. E. by E. of Acapulco, Mexico, November 29, 1937, in 20 fathoms), Cat. No. 37,742; Station 195: D-17 (Port Guatulco, Mexico, December 7, 1937, in 6 fathoms), Cat. No. 37,741; Station 214: D-3 and 4 (14 miles S. by E. of Judas Point, Costa Rica, March 1, 1938, in 50 and 61 fathoms), Cat. No. 38,409.
Family Piiyllodocidae.
Phyllodoce Savigny.
Phyllodoce oculata Ehlers.
Phyllodoce oculata Ehlers, 1887, pp. 135-140; pi. 40, figs. 4-6.
Collected at Station 220: L-2 (Isla Parida, Gulf of Chiriqui, Panama, March 12, 1938, surface light), Cat. No. 38,650; Station 126: D-19 (S. E. of Cedros Island, Mexico, November 10, 1937, in 25 fathoms), Cat. No. 3,794.
Phyllodoce groenlandica Oersted.
Phyllodoce groenlandica Oersted, 1842-43. Teste McIntosh. McIntosh, 1908-10, pp. 86-88; pi. 58, fig. 5; pi. 68, figs. 4-6; pi. 78, fig. 7.
Collected at Station 223: L-l (Bahia Hermosa, Coiba Island, Panama, March 19, 1938, at sur- face light), Cat. No. 38,760.
Eulalia magnapupula sp. nov.
(Text-ligures 13-17).
Characterized by very large eyes and short
22 Zoologica: New York Zoological Society [XXVI: (3
tentacles and cirri. Two specimens, of which the type is the larger but is incomplete. The smaller is 57 mm. long and in the anterior body region is 4 mm. in diameter to the ends of the setae. The posterior end is very narrow and possibly regenerating.
In the preserved material the anterior margin of the prostomium is rounded, the lateral margins straight and running directly into the eyes (Text-fig. 13). The paired tentacles are heavy cones hardly longer than wide, only the anterior ones visible from the dorsal surface. The median tentacle is inconspicuous and is situated at about the middle of the dorsal prostomial surface. The eyes are very large, either one being larger than the exposed portion of the prostomium. Their lenses are visible only from the sides. The ten- tacular cirri are one pair on the first somite, two pairs on the second and one pair on the third (Text-fig. 14). The cirrophores of dorsal one on second and third pairs are heavy and about as long as the styles. The style of the third pair is the longest but this barely reaches the third somite. The eyes are dark brown, the peristomial surface is marked by brown pigment, cirrophores of tentacular cirri dark brown, styles colorless. Anteriorly the body color is light brown with a tendency toward a transverse dark band near the anterior margin of the somite and a darker spot on the anterior margin of the parapodium. This latter spot becomes more prominent posteriorly, and posterior to about the twenty-fifth somite is carried on a definite rounded lobe. The flattened dorsal cirri are more or less spotted with brown. Anteriorly on the ventral surface the pigmenta- tion is diffuse, while posteriorly there is a dark spot at the base of each parapodium. On the midventral portion of each somite is an uncol- ored spot shaped like a thickened H which is prominent against the diffuse brown of the general surface. Neither specimen retains the anal cirri.
The parapodium is conical (Text-fig. 15), the posterior lip the longer and terminating in a fila- mentous tip, the acicula protruding from the surface by the side of this filament. Between the two lips arises a fan-shaped seta tuft. The dorsal cirrus is broad-lanceolate on a heavy cirrophore and reaches about as far as the end of the fila- ment on the setal lobe. The ventral cirrus is shorter than the setal lobe, heavy, with recurved tip. There are two kinds of setae, the first simple, bluntly rounded and slightly curved at the tip (Text-fig. 16), the other compound, with a long basal joint, the terminal joint slender and sharp-pointed (Text-fig. 17).
In the type the pharynx is protruded to a dis- tance equal (in preserved material), to the length of the first eight somites.
The type was collected at Station 225: T-l (11 miles S. W. by S. of Jicaron Island, Panama, March 20, 1938, in 500 fathoms), Cat. No. 38,767. Another specimen was taken at Station 227 : T-l (20 miles S. W. of Morro de Puercos, Panama, March 21, 1938, in 500 fathoms), Cat. No. 38,789. The type is No. 38,767 in the collection of the
Department of Tropical Research of the New York Zoological Society.
Family Tomopteridae.
Tomopteris Eschscholtz.
Tomopteris opaca Treadwell.
Tomopteris opaca Treadwell, 1928, pp. 463, 464, fig. 178: fig. 29.
Collected at Station 210: T-10 (20 miles south of Cape Blanco, Costa Rica, February 27, 1938, in 500 fathoms), Cat. No. 38,391. Station 233: T-l (55 miles south of Cape Corrientes, Colombia, April 3, 1938, in 500 fathoms), Cat. No. 38,908.
Family Typhoscolecidae.
Travisiopsis Levinsen. Travisiopsis atlantica Treadwell.
Travisiopsis atlantica Treadwell, 1936, pp. 62, 63; figs. 30-33.
Collected at Station 227 : T-l (20 miles S. W. of Morro de Puercos, Panama, March 21, 1938, in 500 fathoms), Cat. No. 38,789.
Family Leodicidae.
Leodice Savigny.
Leodice longisetis Webster.
Leodice ( Eunice ) longisetis Webster, 1884, pp. 317, 318; pi. 10, figs. 46-49.
Collected at Sihuatenejo, Mexico, November 24, 1937, in coral, Cat. No. 37,266.
Leodice paloloides Moore.
Leodice paloloides Moore, (?) 1919, pp. 246-249; pi. 7, figs. 5-7.
Collected at Sihuatanejo, Mexico, November 24, 1937, in coral, Cat. No. 37,266A.
Diopatra Aud. et M. Ed.
Diopatra ornata Moore.
Diopatra ornata Moore, 1911, pp. 273-277; pi. 18, figs. 77-85.
Collected at Station 196: D-1S (Tangola- Tangola Bay, Mexico, December 13, 1937, in 30 fathoms), Cat. No. 37,645A.
Hyalinoecia Malmgren. Hyalinoecia juvenalis Moore.
Hyalinoecia juvenalis Moore, 1911, pp. 277- 280; pi. 18, figs. 86-95.
Collected at Station 203: D-2 (Port Parker, Costa Rica, January 20, 1938, in 10 fathoms), Cat. No. 38,109A.
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Arabella Grube.
Arabella pacifica sp. nov.
(Text-figures 18-21).
The body is broken about at its middle but the entire animal is preserved, the total length being 160 mm. The body width is 3 mm., the pro- stomial width 1.3 mm. The prostomium is rounded (Text-fig. 18) and no eyes are visible. The anterior parapodia are very small, later ones increase in size but the posterior ones are small. There are two anal cirri, these being short with rounded ends. On the parapodia are prominent dorsal lobes extending to the ends of the setae. Setae are of only one kind (Text-fig. 19), having slender stalks widened and geniculate toward the extremities with very sharp apices and a pair of toothed wings at the bend. In profile only one of the wings is visible and unless slightly tilted the marginal denticulations do not appear. In each parapodium are three aciculae protruding only very slightly from the surface.
All mouth parts jet black. In the maxilla the terminal plate on either side has only one tooth (Text-fig. 20). No. 2 has on either side a 6- toothed plate; No. 3 on either side 7 teeth. The forceps are heavy and overlie the proximal plates so that without destroying the specimen it was not possible to determine the precise number of teeth in each of the latter, but they extend as far as the forceps base and are toothed for the greater part of their length. Apparently also the inner margin of the forceps is toothed. The basal rods are very long, less than half of them being shown in the figure The mandible is rectangular with a forked base (Text-fig. 21).
The type was collected at Sihuatanejo, Mexico, November 24, 1937, in coral, Cat. No. 37,266, and is in the collection of the Department of Tropical Research of the New York Zoological Society.
Family Amphictenidae.
Pectinaria Lamarck.
Pectinaria gouldii Verrill.
Pectinaria gouldii Verrill, 1873, p. 612; figs 87, 87A.
Collected off Ballenas Bay, Gulf of Nicoya, Costa Rica, February 26, 1938, in mangrove mud, Cat. No. 38,359A.
Family Opheliidae.
Ammotrypane Rathke. Ammotrypane bermudiertsis Treadwell.
Ammotrypane bermudiensis Treadwell, 1936, pp. 60, 61; figs. 24-26.
Collected at Station 208: D-3 (Piedra Blanca Bay, Costa Rica, February 5, 1938, in 4 fathoms), Cat. No. 38,187A.
Family Capitellidae.
Notomastus Sars.
A single specimen of undetermined species was collected at Station 126: D-16 (East of Cedros Island, Mexico, November 10, 1937, 42 fathoms), Cat. No. 3,781.
Family Glyceridae.
Hemipodus Quatrefages.
Hemipodus mexicanus Chamberlin.
Hemipodus mexicanus Chamberlin, 1919, pp. 349-350; pi. 63, figs. 2-3.
Collected at Station 126: D-16 (East of Cedros Island, Mexico, November 10, 1937, in 42 fathoms), Cat. No. 3,781A.
Family Chlorhaemidae.
Stylarioides Della Chiaje.
Stylarioides sp.?
Collected at Station 221 : D-5 (Gulf of Chiriqui, Panama, March 13, 1938, in 35-40 fathoms), Cat. No. 38,659A.
Family Terebellidae.
Terebella Linnaeus.
Terebella gorgonae Munro.
Terebella gorgonae Munro, 1933 A, pp. 1070, 1071, fig. 18.
Collected at Station 203: D-9 (Port Parker, Costa Rica, January 22, 1938, in 2 fathoms), Cat. No. 38,111.
Terebellides Sars.
Terebellides stroemi Sars.
Terebellides stroemiSavs, 1835. Teste McIntosh. McIntosh, 1922, pp. 209-215; pi. 120, fig. 3; pi. 127, fig. 5.
Collected at Station 126: D-16 (East of Cedros Island, Mexico, November 10, 1937, in 42 fath* oms), Cat. No. 3,781A.
A single specimen of an empty tube of a tere- bellid, strongly resembling that of Lanice figured by McIntosh (1885, pi. 49, fig. 4), was collected at Station 224: D-3 (Hannibal Bank, Panama, March 20, 1938, in 35 fathoms), Cat. No. 38,755.
Family Sabellidae.
Sabella Linnaeus.
Sabella melanostigma Schmarda.
Sabella melanostigma Schmarda, 1861, p. 36. Elders, 1887, p. 263.
Collected at Sihuatanejo, Mexico, March 24, 1937, in coral, Cat. No. 37,266A.
24
Zoologica: New York Zoological Society [XXVI : G
Bibliography.
Chamberlin, R. V.
1919. The Annelida Polychaeta. Memoir Mu- seum of Comparative Zoology, Harvard College, vol. 48, pp. 1-514; pis. i-80.
Ehlers, Ernst
1864-68. Die Borstenwurmer, pp. 1-722; pis. 1- 24.
1887. Florida Anneliden. Memoir Museum of Comparative Zoology, Harvard College, vol. 15, pp. 1-335; pis. 1-60.
Fauvel, Pierre
1916. Resultats des Compagnes Scientifiques ac- complies sur son yacht par Albert ler, Prince Souverain de Monaco. Monaco, Fasc. 48, pp. 1-152; pis. 1-9.
Grube, A. E.
1856. Annulata Oerstediana. Vitensk. Meddel. fra d. Naturh. Foren. Kjobenh, pp. 44-62.
Horst, R.
1912. Polychaeta errantia. Siboga Exp. Mono- graphs, vol. 24A, 43 pp.; 10 pis., Pt. 1, Amphinomidae.
Kinberg, J. G. H.
1857. Ofversigt K. Vetensk. Akad. Fork., pp. 11- 14.
1865. Ofversigt K. Vetensk. Akad. Forh., pp. 167-180.
McIntosh, W. C.
1885. Challenger Expedition Reports, vol. 12, pp. i-xxxvi; 1-554; pis. 1-55; 1A-39A.
1908-10. Monograph of the British Annelids. Ray Society Publication, vol. 2, Nephthy- didae to Ariciidae; pp. 1-524; pis. 43-87.
Moore, J. Percy
1 909. Polychaetous annelids from Monterey Bay and San Diego, California. Proc. Acad. Nat. Science, Philadelphia, vol. 61, pp. 235-295; pis. 7-9.
1911. Polychaetous annelids dredged by the U. S. S. Albatross off the coast of Southern California in 1904. III. Euphrosynidae- Goniadidae. Proc. Acad. Nat. Science, Philadelphia, vol. 63, pp. 234-318; pis. 15-21.
Munro, C. C. A.
1933. Polychaeta errantia collected by Dr. C. Crossland at Colon, in the Panama region and the Galapagos Is. Proc. Zool. Soc. London, pt. 1, pp. 1-96; text-figs. 1-36. 1933A. Polychaeta sedentaria collected by Dr. C. Crossland at Colon in the Panama region and the Galapagos Is. Proc. Zool. Soc. London, pt. 4, pp. 1039-1092; text-figs. 1-31.
Schmarda, Ludwig
1861. Neue wirbellose Thiere. Bd. 1, Hft. 2, pp. 1-164; pis. 16-37.
Treadwell, A. L.
1906. Polychaetous annelids of the Hawaiian Is. Bull. U. S. Fish Commission for 1903, pt. 2, pp. 1145-1181, 81 figs.
1928. Polychaetous Annelids from the Arcturus Oceanographic Expedition. Zoologica, vol. 8, no. 8, pp. 449-485, figs. 177-179.
1936. Polychaetous annelids from the vicinity of Nonsuch Id. Bermuda. Zoologica, vol. 21, pt. 1, pp. 49-68; 3 pis.
1937. Polychaetous Annelids from the West Coast of Lower California, the Gulf of California and Clarion Island. Zoologica, vol. 22, pt. 2, pp. 139-160, 2 pis.
Verrill, A. E.
1873. Invertebrate Animals of Vineyard Sound. Report U. S. Fish Commission for 1872. Annelids, pp. 580-622; pis. 10-17.
Webster, H. E.
1884. Annelida from Bermuda. Bull. U. S. National Museum, no. 25, pp. 305-327, 12 pis.
1941]
Treadwell: Polychaetous Annelid* from Bermuda Plankton
7.
Plankton of the Bermuda Oceanographic Expeditions. X.
Polychaetous Annelids from Bermuda Plankton, with Eight Shore Species, and Four from Haiti.1
Aaron L. Treadwell Department of Zoology, Vassar College.
(Text-figures 1-9).
Con . 25
. 25
. 26
. 26
. 26 . 26 . 27
. 27
. 28
. 2S
. 28 . 28 . 28
TENTS.
Family Leodicidae
Leodice stigmatura Verrill 28
Leodice culebra Treadwell 28
Leodice mutilata Webster 28
Family Syllidae
Autolytus bidens sp. nov 28
Iiaplosyllis gula Treadwell 29
Family Amphictenidae
Pectinaria gouldii Verrill 29
Family Opheliidae
Ammotrypane bermudiensis Treadwell 29
Family Glyceridae
Telake epipolasis Chamberlin 29
Family Terebellidae
Eupolymnia magnified Webster 29
Family Sabellidae
Dasychonopsis conspersa Elilers 29
Family Serpulidae
Spirobranchus tricornis (Morch) Elders . 29
Bibliography 29
Introduction
Systematic Account.
Fandly Ampldnomidae Hermodice caruncuiata Kinberg . .
Family Polynoidae Lepidonotus pilosus Treadwell . . .
Family Sigalionidae
Acanthicolcpis longicirrata sp. nov.
Family Phyllodocidao
Eulalia megalops Verrill
My slides gracilis sp. nov
Lopadorhynchus uncinatus Fauvel
Family Alciopidae
Vanadis fuscapunclata Treadwell .
Fandly Tomopteridae
Tomopteris longiselis Treadwell . .
Fandly Typldoscolecidae
Travisiopsis atlantica Treadwell .
Fandly Nereidae
Nereis bairdii Webster
Nereis mirabilis Kinberg Nereis agassizi Ehlers
[This is the tenth of a series of papers dealing with the plankton content of a series of nets drawn through a cylinder of water off the coast of Bermuda on the Bermuda Oceanographic Expeditions of the Department of Tropical Research under the direction of Dr. William Beebe. Full details as to this circle of water, and of the dates, depths, etc., of the nets will be found in Zoologica, Vol. XIII, Nos. 1, 2 and 3, pp. 1-45, and Zoologica, Vol. XXI, No. 3, pp. 69-73.]
Introduction.
The following is an account of 23 species of polychaetous annelids collected primarily at Bermuda on the Bermuda Oceanographic Ex-
1 Contribution No. 614, Department of Tropical Re- search, New York Zoological Society.
Contribution from the Bermuda Biological Station for Research, Inc.
peditions of the Department of Tropical Research of the New York Zoological Society, plus materi- als relating to specimens collected on the Haitian Expedition of the Department in 1927. Three new species are described, the types of which are deposited in the collections of the Department of Tropical Research.
Systematic Account.
Family Amphinomidae.
Hermodice Kinberg.
Hermodice caruncuiata Kinberg.
Hermodice caruncuiata Kinberg, 1857, p. 13.
Collected at Cooper’s Island, Bermuda, in mud, Sept. 11, 1931, Cat. No. 312,029. Nonsuch Island, Bermuda in shallow water, July 23, 1929, Cat. No. 29,135.
[XXVI: 7
26 Zoologica: New York Zoological Society
Family Polynoidae.
Lepidonotus Leach.
Lepidonotus pilosus Treadwell.
Lepidonotus pilosus Treadwell, 1937, pp. 141- 143, pi. 1, figs. 1-7.
Collected at Bizoton, Port-au-Prince Bajq Haiti, March 22, 1927.
Family Sigalionidae.
Acatithicolepis Norman.
Acanthicolepis longicirrata sp. nov.
(Text-figures 1-4).
Characterized by the long tentacles and cirri and by the large eyes. As seen from above the pigmented borders of the two eyes on either side are in contact (Text-fig. 1) and appear to run together, forming a heavy pigmented border to the prostomium. The lens of the posterior eye points laterally, thus seeming to bend the pig- mented band toward the dorsal surface. The lens of the anterior eye is not visible from above.
Length 15 mm., width of prostomium 1 mm., greatest body width to parapodial bases 4 mm. in region of 9th somite. At first gradually, later more rapidly, the body tapers to about 0.5 mm. at the posterior end. Only one elytron remains and the preservation is such that it is impossible to be certain of the elytrophore count in later somites but the number is apparently 18. The prostomium is somewhat broader than long, each half ending on its anterior margin in a well marked peak. The cirrophore of the median tentacle is heavy, set into a shallow depression between the two prostomial halves. The style of the median tentacle is about the length of the palps, these 3 mm. long, colorless and curved, the apices diverging. Cirrophores of the lateral tentacles small, styles slender, reaching to about the middle of the palps. Only one tentacular cirrus and one dorsal cirrus remain, these being about as long as the palps. Each cirrus has a central opaque white core, the remainder being- translucent. Apparently the elytra originally covered the dorsal surface but only one remains. This is so transparent as to be easily overlooked. On its surface are numerous, evenly distributed, low spines visible under a 40 diameter magnifica- tion. Its outline is approximately circular.
In a parapodium taken from in front of the middle of the body (Text-fig. 2) the notopodium is shorter than the neuropodium and the latter when seen from above has an inflated appearance, its longitudinal diameter being greater than that of the notopodium. The notopodial acicula is shorter but slightly heavier than the neuropodial, the former being covered nearly to its apex by a symmetrical tissue outgrowth. A similar out- growth covers the neuroacicula but there is in addition a papilla lying parallel to the acicula end (Text-fig. 2). The ventral cirrus is slender and elongated, extending for nearly half its length beyond the apex of the setal lobe. The
notosetae are heavier than the neurosetae and form a diverging tuft which extends almost vertically from the notopodium. They are of two kinds, one straight and sometimes very heavy, the others shorter and curved. Both have transverse rows of plates whose margins seem not to be particularly toothed. The neurosetae are more numerous and more slender. The dorsal ones in the tuft are slender, have very sharp points and alternately arranged rows of toothed plates (detail in Text-fig. 3). Ventral to these are fewer and larger ones which enlarge toward the ends and then narrow to acute apices. A row of toothed plates lies along one margin of the tapered portion (Text-fig. 4).
The type was collected in Net 1,503, 600 fath- oms deep, off Bermuda, July 25, 1934. Others were taken in Net 1,316, 800 fathoms, off Ber- muda, Sept. 17, 1931, Cat. No. 312,135. It was also taken at Station 114: T-5, 500 fathoms, in the Hudson Gorge, 125 miles off New York City, July 8, 1928. The type is No. 3,465 in the col- lection of the Department of Tropical Research of the New York Zoological Society.
Family* Phyllodocidae.
Eulalia Savigny.
Eulalia megalops Verrill.
Eulalia megalops Verrill, 1900, p. 601.
Collected in Castle Harbor, Bermuda, August 13, 1931, Cat. No. 311,247. Taken in a bivalve shell in coral.
Mystides Theel.
Mystides gracilis sp. nov.
(Text-figures 5-7).
A slender species represented only by an in- complete specimen. What remains is 62 mm. long and about 1.5 mm. in diameter in greatest width. The prostomium (Text-fig. 5) has the form of a cone with rounded apex, the sides nearly straight lines. The eyes are large and have prominent lenses. Behind the prostomial margin is a small tubercle. The tentacles are about one- third as long as the prostomium. There are four pairs of tentacular cirri arranged according to the generic formula. The third pair are the longest, reaching somite 7 ; the dorsal of the second pair reaches to somite 5. Except for faint transverse lines on the anterior dorsum, the body is colorless. In most of the anterior region the dorsal cirri have been lost but those that remain are very small, barely reaching to the end of the setal lobes. Posterior ones (Text-fig. 6) are much larger, are rectangular in form and carried on heavy bases. In the setal lobe there is a slightly bifid posterior lip and a rounded one coming to the surface between them. In each parapodium there are about ten setae having rather heavy basal joints, enlarged and spiny at the ends. The terminal joints are long and slender, curved, and toothed on the concave margins (Text-fig. 7). The ventral cirri are longer than the setal lobe, have ovate outlines and acute apices.
1941]
Treadwell: Polychaelous Annelids from Bermuda Plankton
27
Text-figures 1-9.
1-4. Acanthicolepis longicirrata sp. nov. 1, head X 12; 2, parapodium X 23; 3, detail of stalk of neuroseta X 180; 4, neuroseta X 85. 5-7. Mysti- des gracilis sp. nov. 5, head X 15; 6, parapodium X 33; 7, seta X 250. 8, Nereis agassizi Ehlers.
Parapodium X 23. 9, Autolytus bidens sp. nov.
Head X 45.
The type was collected in Net 1,179, off Bermuda at the surface, August 14, 1931, Cat. No. 311,288, and is in the collection of the Department of Tropical Research of the New York Zoological Society.
Lopadorhynchus Grube.
Lopadorhynchus uncinatus Fauvel.
Lopadorhynchus uncinatus Fauvel, 1916, pp. 57-61, pi. 1, figs. 2-3; pi. 4, figs. 4-14.
Collected at Bermuda in the following nets: Net 1,321, 50 fathoms, Sept. 18, 1931, Cat. No. 312,166, color, pinkish tan; Net 1,337, 600 fath- oms, Oct. 29, 1931, color orange.
Family Alciopidae.
Vanadis Claparede.
Vanadis fuscapunctata Treadwell.
Vanadis fuscapunctata Treadwell, 1906, pp. 1159-1160, figs. 29-31.
Collected in Bermuda in the following: Net 10, 400 fathoms, April 9, 1929, Cat. No. 2932; Net 1,175, 600 fathoms, Aug. 14, 1931, Cat. No. 311,761, color transparent, eyes scarlet; Net 1,262, 700 fathoms, Sept. 4, 1931, Cat. No. 311,807; Net 1,264, 900 fathoms, Sept. 4, 1931, Cat. No. 311,821, color dirty tan in general, eyes coral red; Net 1,275, 1,000 fathoms, Sept. 7, 1931, Cat. No. 311,866, color white, eyes scarlet; Net 1,308, 100 fathoms, Sept. 16, 1931, Cat. No. 312,073, color olive, eyes red; Net 1,321, 50 fathoms, Sept. 18, 1931, Cat. No. 312,167, color lemon yellow, eyes coral red; Net 1,508, 100 fathoms, Aug. 14, 1934, Cat. No. 34,256.
The following field-notes were made upon specimen No. 31,472 (Net 1,050, 25 fathoms, July 6, 1931), 23 mm. long:
Color: Eyes coral red with gleaming, brighter centers which are at the base of a tiny projecting crystal dome. Otherwise the animal is entirely transparent except for a yellowish, reddish, brownish or blackish spot behind the base of each lateral appendage. These spots are lightest and brightest when the worm is active or when it has been exposed for some time to bright light. There is no noticeable change in their size, except possibly a slight contraction after the worm was placed in the darkness of a refrigerator. The eyes paled only slightly when the worm was kept in darkness. As the worm weakened a growing opaqueness was noticeable.
Movements: Locomotion is principally by means of the short, three-leaved, shamrock-like paired appendages which, on alternate sides, are thrown abruptly forward and back so that the worm, seen from above, has a ridiculous sort of waddle. It seems to move either ahead or in reverse with equal facility and no apparent change of method. When greatly excited it shoots through the water with tremendous con- tortions, twistings and loopings of the entire body.
The partitions between the segments, as trans- parent as the body wall, are pierced by holes which, more or less rhythmically, though not in unison, expand almost to full diameter of the segment and contract nearly to pinheads. The funnel-shaped proboscis is likewise contractile.
This worm remained alive in the Bermuda laboratory for two days. It was kept in a qui- escent condition in the refrigerator most of the time, but was revived at intervals of a few hours in the warm air of the laboratory. About five to ten minutes were required for it to show signs of life.
[XXVI: 7
Zoologica: New York Zoological Society
28
Family Tomopteeidae.
Tomopteris Eschscholtz.
Tomopteris longisetis Treadwell.
Tomopteris longisetis Treadwell, 1936, pp. 58-59, figs. 18-21.
Collected in Bermuda, Net 1,332, 600 fathoms, Oct. 28, 1931, Cat. No. 312,227, color white.
Fragments and young of toinopterids were col- lected in other nets at Bermuda, but none were identifiable.
Family' Typhoscolecidae.
Travisiopsis Levinsen.
Travisiopsis atlantica Treadwell.
Travisiopsis atlantica Treadwell, 1936, pp. 62, 63, figs. 30-33.
Collected in Bermuda in the following nets: Net 793, 700 fathoms, July 9, 1930, Cat. No. 30,477; Net 869, 1,000 fathoms, Sept. 10, 1930, Cat. No. 30,844, color orange yellow; Net 881, 600 fathoms, Sept. 12, 1930, Cat. No. 30,904, color orange yellow; Net 956, 1,000 fathoms, Sept. 28, 1930, Cat. No. 301,307; Net 1,258, 900 fathoms, Sept. 3, 1931, Cat. No. 311,778; Net 1,264, 900 fathoms, Sept. 4, 1931, Cat. No. 311,820, color transparent white.
Family Nereidae.
Nereis Cuvier.
Nereis bairdii Webster.
Nereis bairdii Webster, 1884, pp. 312-313, pi. 8, figs. 22-28.
Collected at the surface at Bermuda as follows : Net 982, surface, May 19, 1931, Cat. No. 3,124; Net 1,179, surface, Aug. 14, 1931, Cat. No. 311,286; dip net at night-light, Aug. 27, 1937. Those from Net 982 are in the heteronereis stage.
Nereis mirabilis Kinberg.
Nereis mirabilis Kinberg 1865, p. 170.
Collected in Bermuda as follows: Net 982, surface, May 19, 1931, Cat. No. 3,124A; Net 1,332, 600 fathoms, Oct. 28, 1931, Cat. No. 312,286.
Nereis agassizi Ehlers.
(Text-figure 8).
Nereis agassizi Ehlers, 1868, pp. 542-546, pi. 23, fig. 1. ‘
A single specimen, doubtfully identified as this species. Its most characteristic features are the dark parapodial glands and the single heavy spine in each parapodium lying almost in contact with the notopodial acicula on its dorsal surface (Text-fig. 8) . This also conforms with reasonable accuracy to the brief description of N. kobiensis as given by McIntosh (1885, pp. 210-212, pi. 34, figs. 3-6; pi. 16a, figs. 2-4). I was unable to get
a good view of the jaw apparatus which would have been confirmatory. Both of these species have some resemblances to N. dumerilii Aud. et M. Ed., but no diagnoses that I have seen of the latter species mention the heavy spine.
Collected in Bermuda, Net 1,237, 700 fathoms, Aug. 29, 1931, Cat. No. 311,651, color orange- yellow.
Family Leodicidae.
Leodice Savigny.
Leodice stigmatura Verrill.
Leodice stigmatura Verrill, 1900, pp. 641-643.
Collected in tidepool on Nonsuch Island, Bennuda, April 23, 1929, Cat. No. 2,945.
Leodice culebra Treadwell.
Leodice ( Eunice ) culebra Treadwell, 1901, p. 197, fig. 37.
Dredged off Nonsuch Island, Bermuda, 2 fathoms, Nov. 4, 1931, Cat. No. 312,339.
Leodice mutilata Webster.
Leodice ( Eunice ) mutilata Webster, 1884, pp. 315-316, pi. 9, figs. 36-40.
Collected in coral, Castle Harbor, Bermuda, May 1929.
Family Syllidae.
Autolytus Clrube.
Autolytus bidens sp. nov.
(Text-figure 9).
In a bottle labeled “luminous worms, from Castle Harbor, Bermuda” were numerous frag- ments of an Autolytus that is evidently of a new species. No entire individuals wrere present and I have no information concerning absolute size or differences in body regions. The prostomium (Text-fig. 9), is broader than long, its posterior margin deeply indented and almost its entire dorsal surface taken up by the eyes of which the anterior pair is the larger. They are dark brown in color and very conspicuous. The median tentacle is from six to eight times as long as the prostomium, lateral tentacles much shorter and a little more slender. Tentacular cirri about as long as the median tentacle. The first few dorsal cirri are long, later ones shorter but all longer than body width. Width of prostomium about 2/3 mm. The pharynx extends through six somites, the brown oesophagus through two, the stomach through seven. In the type the first twenty-one somites have only compound setae while later ones have in addition a tuft of long and extremely slender simple ones. With the appearance of the longer setae the antero-postero diameter of the parapodia increases, giving them a swollen appearance. There was no indication of sex products.
The compound setae are veiy small, the basal joint slightly widened and beveled at the end.
1941]
Treadwell : Polychaetous Annelids from Bermuda Plankton
29
The terminal joint is extremely short and has a terminal tooth and a smaller one at about the middle of the concave surface.
Collected at surface, Nonsuch Island, Bermu- da, Nov. 16, 1931. Type, No. 312,351, Depart- ment of Tropical Research, New York Zoological Society.
Haplosyllis Langerhans.
Haplosyllis gula Treadwell.
Haplosyllis gala Treadwell, 1924, pp. 11, 12, figs. 19-23.
Dredged in shallow water, Isle de Gonave, Haiti, June 1, 1927, Cat. No. 272.
Family Amphictenidae.
Pectinaria Lamarck.
Pectinaria gouldii Verrill.
Pectinaria gouldii Verrill, 1873, p. 612, figs. 87, 87a.
Collected in Castle Harbor, Bermuda, Nov. 2, 1931, 2 fathoms, Cat. No. 312,342.
Family Opheliidae.
Ammotrypane Rathke.
Ammotrypane bermudiensis Treadwell.
Ammotrypane bermudiensis Treadwell, 1936, pp. 60, 61, figs. 24-26.
Collected at surface off Nonsuch Island, Bermuda, May 12, 1931, Cat. No. 317. Speci- mens dredged at 2 fathoms, off Nonsuch Island, Bermuda, Aug. 25, 1931, Cat. No. 311,675, and Oct. 3, 1931, Cat. No. 312,234.
Family Glyceiiidae.
Telake Chamberlin.
Telake epipolasis Chamberlin.
Telake epipolasis Chamberlin, 1919, pp. 346- 348, pi. 63, figs. 4-8; pi. 64, fig. 1.
Collected at Bermuda, Net 1,179, surface, Aug. 14, 1931, Cat. No. 311,287.
Family Terebellidae.
Eupolymtiia Verrill. Eupolymnia magnified Webster.
Eupolymnia ( Terebella ) magnified Webster, 1884, p. 324, pi. 11, figs. 58-60.
Collected in Bermuda as follows: Nonsuch Island, tidepools, Apr. 23, 1929, Cat. No. 2,945A; Nonsuch Island, tidepools, Aug. 22, 1929, Cat. No. 29,158; surface at night, near Nonsuch Island, Sept. 13, 1931, Cat. No. 311,996.
Family Sabellidae.
Dasychonopsis Bush.
Dasychonopsis conspersa Ehlers.
Dasychonopsis ( Dasychone ) conspersa Ehlers, 1887, pp. 226-270, pi. 54, figs 1-6.
From bottom of old barge, Bizoton, Port-au- Prince Bay, Haiti, Cat. No. 27,212.
Family Serpulidae.
Spirobranchus Blainville.
Spirobranchus tricornis (Morch) Ehlers.
Spirobranchus tricornis Ehlers, 1887, pp. 292- 295; pi. 57, figs. 8-15.
Collected at Lamentin Reef, Port-au-Prince Bay, Haiti, Apr. 26, 1927, Cat. Nos. 27,379, 27,385, color red with golden setae.
Bibliography.
Chamberlin, R. V.
1919. The Annelida Polychaeta. Memoir Mu- seum. Comparative Zoology, Harvard College, vol. 48, pp. 1-514, pis. 1-80.
Ehlers, Ernst
1864-1868. Die Borstenwiirmer, pp. 1-722, pis. 1-24.
1887. Florida Anneliden. Memoir Museum Com- parative Zoology, Harvard College, vol. 15, pp. 1-335, pis. 1— 60.
Fauvel, Pierre
1916. Residtats des Campagnes Scientifiques ac- complies sur son yacht par Albert ler, Prince Souverain de Monaco. Fasc. 48, pp. 1-152, pis. 1-9.
Grube, A. E.
1856. Annulata Oerstediana. Vitensk. Meddel. fra d. Naturh. Foren. Kjobenh., pp. 44-62.
Horst, R.
1912. Polychaeta errantia. Siboga Exp. Mono- graphs, vol. 24A, 43 pp., 10 pis., pt. 1, Amphinomidae.
Kinberg, J. G. H.
1857. Ofversigt. K. Vetensk. Akad. Forh., pp. 11- 14.
1865. Ofversigt. K. Vetensk. Akad. Forh., pp. 167— 180.
McIntosh, W. C.
1885. Challenger Expedition Reports, vol. 12, pp. i-xxxvi, 1-554, pis. 1-55, 1A-39A.
1908-1910. Monograph of the British Annelids, vol. 2, Ray Society Publication, Nephthy- didae to Ariciidae, pp. 1-524, pis. 43-87.
1922. Monograph of the British Annelids, vol. 4, Ray Society Publication, Hermellidae to Sabellidae, pp. 1-250, pis. 112-127.
30
Zoologica: New York Zoological Society
[XXVI: 7
Moore, J. Percy
1909. Polychaetous annelids from Monterey Bay and San Diego, California. Proc. Acad. Nat. Sci., Philadelphia, vol. 61, pp. 235- 295, pis. 7-9.
1911. Polychaetous annelids dredged by U. S. S. Albatross off the coast of Southern Cali- fornia in 1904. Ill, Euphrosynidae- Goniadidae. Proc. Acad. Nat. Sci. Phila- delphia, vol. 63, pp. 234-318, pis. 15-21.
Munro, C. C. A.
1933. Polychaeta errantia collected by Dr. C. Crossland at Colon, in the Panama region and the Galapagos Islands. Proc. Zool. Soc. London, pt. 1, pp. 1-96, figs. 1-36.
1933 A. Polychaeta sedentaria collected by Dr. C. Crossland at Colon, the Panama region and the Galapagos Islands. Proc. Zool. Soc. London, pt. 4, pp. 1039-1092, figs. 1-31.
Schmarda, Ludwig
1861. Neue wirbellose Thiere. Bd. 1, Hft. 2, pp. 1-164, pis. 16-37.
Treadwell, A. L.
1901. Polychaetous annelids of Porto Rico. Bull. U. S. Fish Comm, for 1900, vol. 2, pp. 181-210, 81 figs.
1906. Polychaetous annelids of the Hawaiian Islands. Bull. U. S. Fish Comm, for 1903 pt. 3, pp. 1145-1181, 81 figs.
1924. Polychaetous annelids collected by the Barbados- Antigua Expedition from the University of Iowa in 1918. Univ. of Iowa Studies in Natural History, vol. 10, no. 4, pp. 1-23, 2 pis.
1928. Polychaetous annelids from the Arcturus Oceanographic Expedition. Zoologica, vol. 8, no. 8, pp. 449-485, figs. 177-179.
1936. Polychaetous annelids from the vicinity of Nonsuch Island, Bermuda. Zoologica, vol. 21, pt. 1, pp. 49-68, pis. 1-3.
1937. Polychaetous annelids from the West Coast of Lower California, the Gulf of California and Clarion Island. Zoologica, vol. 22, pt. 2, pp. 139-160, 2 pis.
Verrill, A. E.
1873. Invertebrate Animals from Vineyard Sound. Report U. S. Fish Comm, for 1872, Annelids, pp. 580-622, pis. 10-17.
1900. Additions to the Turbellaria, Nemertina and Annelida of the Bermudas. Trans. Conn. Acad. Sci., vol. 10, (annelids), pp. 598-669.
Webster, H. E.
1884. Annelida from Bermuda. Bull. U. S. Nat. Mus., 25, pp. 305-327, 12 pis.
1941]
Hollister: Caudal Skeleton of Bermuda Shallow Water Fishes
31
8.
Caudal Skeleton of Bermuda Shallow Water Fishes. V. Order Percomorphi: Carangidae.1
Gloria Hollister
Department of Tropical Research
(Text-figures 1-20).
Outline.
Introduction
PAGE
. . 31
Key Opposite page 32
Bermuda Percomorphi Carangidae
Decapterus macarellus 32
Decapterus punctalus 33
Trachinotus palometa . 34
Trachinotus goodei 35
Argyreiosus vomer 37
Trachurops crumenophthalma 38
Chloroscombrus chrysurus 39
Caranx ruber 42
Caranx bartholomaei 42
Caranx crysos 43
Caranx latus 43
Summary
44
Introduction.
This is the fifth of a series of papers dealing with the caudal skeleton of Bermuda fishes. The Carangidae of Bermuda is represented by six genera and twelve species. No specimens are available of Caranx guara, considered uncommon in Bermuda, either in the collection of this de- partment or in the collections of several other institutions. Caranx guara, locally known as “Gwelly,” is seen by fishermen in shallow water but is said to be a shy, wary fish.
This paper deals principally with the adult fishes, as is the case with the four preceding studies of this series, but when young stages were available these were included.
The length of specimens in this paper is stand- ard length unless otherwise stated.
For caudal fin terminology, general bibliog- raphy, and method of preparing specimens for this study, refer to Part I.
The symbols used in the figures are EP, epural; HS, haemal spine; 1, 2, 3, 4, 5, hypurals; IHS, interhaemal spine; INS, interneural spine; NS, neural spine; UN, uroneural; UR, urostyle.
1 Contribution No. 615, Department of Tropical Re- search, New York Zoological Society,
Contribution from the Bermuda Biological Station for Research, Inc.
We are indebted to the American Museum of Natural History for three specimens of Argy- reiosus vomer. I take this opportunity to thank Dr. William Beebe, Director of this Department, and Mr. John Tee-Van, General Associate, for their cooperation.
The drawings are by Miss Janet B. Wilson, who kindly volunteered to do this work.
In Bermuda Carangidae several precaudal vertebrae are neither typical trunk nor typical caudal in structure. In all species these verte- brae have ribs (although in several specimens diminutive) , which is characteristic of the typical trunk vertebrae. Closed haemal arches are also present, a typically caudal character. These precaudals include several modified vertebrae which immediately precede the true caudal.
The structure of the precaudal haemal arch in Trachurops differs radically from that of Chloro- scoitibrus and Caranx and is readily distinguished from these two latter species by the crescent- shaped arch.
In Decapturus macarellus and Decapterus punctatus several precaudals and anterior true caudals are crescent-shaped and arise on the anterior half of their centra. Decapturus is the only species in this study which has the anterior true caudal haemal processes crescent-shaped.
It is of interest to note that the Bermuda Synodontidae is also unlike the families studied in Parts I, II and IV in having several vertebrae in the precaudal region which deviate from the typical trunk and caudal forms. In Synodontidae there are present, between the trunk and caudal, vertebrae lacking ribs (ribs being characteristic of the trunk), and also lacking closed haemal arches with spines, this structure being charac- teristic of the caudal.
In Bermuda Carangidae there is also this devi- ation from what is generally designated typical trunk and typical caudal vertebrae. This differ- ence is found in several precaudal haemals which
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have closed arches typical of the caudal region but lack the haemal spine which is typical of the trunk. Because of these differences the term precaudal centra is used as in Synodontidae.
The key is based on characters of the adult. In this respect it is important to mention, as an example, that in the immature specimen of Chloroscombrus chrysurus, 6 mm., the difference in length of the three short posterior neural and haemal spines and the length of the preceding long pair of spines is not pronounced as it is in the adult. In the mature specimen both the difference in length and shape is conspicuous and is considered a key character.
1. Decapterus macarellus (Cuvier & Valenciennes).
(Text-figure 7).
Diagonostic Characters:
1 interneural and 1 interhaemal arising over the 4th vertebra anterior to the urostyle.
The horizontal length of this posterior inter- neural and interhaemal about one and a half times longer than the anterior oblique part.
Haemal base of first anterior caudal lunar- shaped.
Caudal interneurals and interhaemals more slender than in the other genera.
Third stout posterior neural and haemal spines dagger-shaped and extend obliquely over three quarters of the following vertebra.
Material Studied.
The following description is taken from one specimen caught in Bermuda, Cat. No. 9,139, KOH Cat. No. 604, length 140 mm.
Caudal Osteology.
Urostyle: The urostyle is conical in shape. The posterior end appears to be consolidated on the dorsal surface with the base of the uroneurals and the fifth hypural and on the ventral with part of
the base of the first and second hypurals. The anterior part of the urostyle is identical in form and size with the adjacent posterior part of the penultimate centrum.
Uroneurals: There is one pair of uroneurals. These paired bones extend from the anterior margin of the urostyle to the distal margin of the hypural complex. On dissecting away the caudal rays the dorsal tip appears distinct from the tip end of the fifth hypural with which the uroneurals are fused. Text-figure 9 of a 10 mm. Decapterus punctatus shows the small fifth hypural in relation to the undeveloped uroneurals. Both these bones are only slightly ossified. Where young speci- mens of Carangidae were available for study this same relation of the two bones is found. Text- figures 13, 16, 17 and 18.
Hypurals: In this adult specimen there appear to be four hypural bones; two below and two above the median line. In the 10 mm. Decapterus punctatus, Text-figure 9, the large dorsal hypural is divided almost to the distal margin, indicating that in a slightly younger specimen this single bone of the adult is formed by two separate elements. This condition is found in several other young carangids. Text-figures 16, 17. The first and fifth hypurals are almost identical in size and are complimentary in their distal positions in the marginal complex. The two large median hypurals of the adult are completely separate to the anterior rounded ends which are partly covered by the base of the uroneurals and the projected lateral muscle attachment process of the first hypural. The fifth or dorsal-most hypural is recognized in the adult by the pointed tip adjacent to the end of the fourth hypural. For its entire length, with the exception of this tip, the fifth hypural is fused with the uroneurals, and appears as one with these bones. Younger specimens give the true explanation of the de- velopment and relationship of the fifth hypural and the uroneurals. In the 42 mm. specimen of Decapterus punctatus the fifth hypural is more easily distinguished by the prominent line of junction which is still present between the hy- pural and the uroneurals.
Decapterus macarellus. Tail of 140 mm. specimen showing especially the prolonged pos- terior interneural and interhaemal spines. X 3.52.
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Epurals: There are two epurals. The posterior bone is slender and rod-like and slants obliquely forward and downward from the distal caudal margin to the dorsal edge of the uroneurals. The ventral tip is inserted between the two lateral uroneural bones. The anterior epural is wider than the ventral epural throughout the entire length. Anteriorly, a long finger-like projection extends forward and fills the area above the re- duced neural process of the last centrum. Similar to the smaller epural, part of the ventral tip is inserted between the uroneural bones.
Additional Characters Worthy of Note: This is the only genus of Bermuda Carangidae which has the extremely long and slender posterior inter- neural and interhaemal spines. The anterior and median ends arise near the anterior zygapophyses of the fourth vertebra from the urostyle and the bones extend back and toward the centra almost to the posterior margin of the next centrum. The interneurals and interhaemals, preceding the prolonged posterior pair, are more slender than in the other species studied in this paper.
The precaudal haemal processes and also the first caudal haemals are lunar-shaped and placed on the anterior part of the centra. This develop- ment is similar to Decapterus punctatus.
2. Decapterus punctatus (Agassiz).
(Text-figures 8, 9).
Diagnostic Characters:
2 interneurals and 2 interhaemals arising over the 4th vertebra anterior to the urostyle.
The horizontal length of this posterior pair only a little longer than the anterior oblique part.
Haemal base of first anterior caudal lunar- shaped.
Caudal interneurals and interhaemals not as slender as those of Decapterus macarellus.
Dorsal and ventral fin rays not as slender as those of Decapterus macarellus.
Material Studied.
The following description is taken from three specimens caught in Bermuda, Cat. No. 8,968, KOH Cat. No. 2316, length 10 mm.; KOH Cat. No. 340, length 18 mm.— taken from under a jellyfish; KOH Cat. No. 2315, length 42 mm.
Caudal Osteology.
Urostyle: In the 42 mm. specimen the urostyle is conical in shape and similar to Decapterus macarellus. No definite posterior tip can be seen. In the 10 mm. specimen the upturned posterior end of the urostyle extends beyond the basal end of the fifth hypural. The anterior margin is iden- tical in form with that of the preceding centrum but posteriorly the shape changes radically into a long slender upturned structure. The urostyle is slightly ossified as far as the base of the fifth hypural. Here, there is a heavy line across the urostyle and beyond this there is little ossifica- tion.
Uroneurals: As in Decapterus macarellus, there is a single pair of uroneurals and in the 42 mm. specimen these paired bones are similar in shape and position to those of the above species. In Decapterus punctatus the line of junction between the fifth hypural and the uroneurals is distinct but this has disappeared in the older specimen of the other species. In the 10 mm. Decapterus punctatus the uroneurals are long, slender, curved bones which extend from the hypural margin to the anterior part of the urostyle. Throughout their entire length the uroneurals are separate from the urostyle and the fifth hypural.
Text-figure 8.
Decapterus punctatus. Tail of 42 mm. specimen showing the difference between this species and Decapterus macarellus in the arrangement and proportions of the interneural and interhaemal spines of the posterior groups. X 9.65.
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Decapterus punctatus. Tail of 10 mm. specimen. This stage shows the development of the 3rd and 4th hypurals which are fused in the 42 mm. specimen. The fifth hypural and the uro- neurals are separate bones in this stage. X 45.4.
Hypurals: In the 42 mm. specimen there ap- pears to be four hypurals; two below and two above the median line. In the 10 mm. specimen there are three hypural bones above the median line, which indicates that the large dorsal hypural of mature specimens is a combination of two bones. Also this young specimen has a small slit in the base of the second hypural which probably indicates a one-time ancestral division of this other large hypural bone. In all Bermuda Isospondyli and Iniomi there are at least three hypurals below the median line. In general shape and proportions the hypural complex of the adult Decapterus punctatus resembles that of Decapterus macarellus, with the exception of the identity of the fifth hypural and uroneurals.
Epurals : There are two epurals in the adult, as in Decapterus macerellus, and the shape and pro- portions are similar. In this species the ventral ends are not inserted between the uroneural bones, but this may be an age character. There is no trace of the epurals in the 10 mm. specimen.
Additional Characters Worthy of Note: The posterior pair of interneural and interhaemal spines are conspicuously longer than the preced- ing spines and the oblique part extends posterior- ly for almost the length of the following centrum. This pair is not as long nor as slender as the corresponding pair of Decapterus macarellus. The precaudal haemal processes and also the first caudal haemals are lunar-shaped and placed on the anterior part of the centra.
In the 10 mm. specimen the caudal centra are only moderately spool-shaped and the zyga- pophyses and the neural and haemal processes are undeveloped. The neural and haemal proc- esses are simple, slender bones and there is little differentiation in the development of the four anterior pair of spines. This difference is con- spicuous in the_adult.
3. Trachinotus palometa Regan.
(Text-figure 10).
Diagnostic Characters:
1 long and slender interneural and 1 inter- haemal arising over the 4th vertebra anterior to the urostyle.
17 interneurals in the caudal region.
Bases of haemal processes arising at the center of the centra.
No short or stout posterior neural and haemal spines.
Material Studied.
The following description is taken from one specimen caught in Bermuda, KOH Cat. No. 601, length 119 mm.
Caudal Osteology.
Urostyle: The anterior part of the urostyle is identical in size and shape to the adjacent part of the preceding penultimate centrum. The pos- terior end cannot be seen because it is consoli- dated with the bases of the uroneurals and hypurals. The dorsal surface is covered by the uroneurals and the ventral surface by the hypural bases.
Uroneurals: There appears to be a single pair of uroneurals, the bones of which extend from the anterior dorsal edge of the urostyle to the distal margin of the hypurals. For part of the distal length the line of junction between the fifth hypural and the uroneurals is distinct. In the smaller specimen of Trachinotus goodei these bones appear separate.
Hypurals: In this adult specimen there appear to be four hypural bones; two below and two above the median line. The second large hypural below the median line is solid with the exception
Hollister: Caudal Skeleton of Bermuda Shalloiv Water Fishes
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1941]
of a small oblong hole near the base. In Tra- chinotus goodei of 54 mm. in length, the base is divided and a definite line can be seen which extends for half the length of the hypural bone. In the large dorsal hypural of Trachinotus palometa there is also indication that this hypural was at one time divided because a distinct line extends anteriorly from the distal margin for more than three-quarters of the length of the hypural. In the other species the base of this large dorsal hypural is divided and a narrow slit extends for about one-quarter the length of the bone and does not quite join with the slit extend- ing from the distal margin. In the species under discussion the fifth or dorsal-most hypural is closely associated with the uroneurals but each can be identified at their dorsal extremity by distinct and separate pointed tips and a line which extends anteriorly for almost half the length. From here the two are fused. In the other species this fifth hypural is more distinct. Hypural numbers have been omitted from this illustration because of the inclusion of the caudal fin rays; for hypural reference, see Text-figure 11 of Trachinotus goodei.
Epurals: There are three epurals in this species and genus. The anterior or first epural is the largest, which is true of the adults of all the other species treated in this paper. Anteriorly, there is a broad thin growth which ahnost fills the entire area dorsal to the penultimate centrum and the urostyle. The second and third epurals are long, slender bones and very closely associated.
At both the proximal and distal ends the tips can be distinguished as separate bones. The ventral ends are not inserted between the uroneurals as is the case in Trachinotus goodei. Often this appears as a growth character but the specimen of this species is less than half the size of Tra- chinotus palometa and the tips of the former are inserted.
Additional Characters Worthy of Note: The il- lustration of this species is the only one which includes the caudal fin rays because the variation in the count is slight in the other species of Carangidae and therefore of little importance. Here the count is : dorsal raylets 6 plus 1 1 dorsal rays, and ventral raylets 6 plus 9 ventral rays, making a total of 17 dorsal plus 15 ventral.
4. Trachinotus goodei Jordan & Evermann.
(Text-figure 11).
Diagnostic Characters:
2 broad interneural and interhaemal spines arising over the 5th vertebra anterior to the urostyle.
15 interneurals in the caudal region.
Bases of the haemal processes arising on the anterior half of the centra.
No short or stout posterior neural and haemal spines.
Material Studied.
The following description is taken from one
Text-figure 10.
Trachinotus palometa. Tail of 119 mm. specimen with three epurals. One interneural and one interhaemal spine is associated with the 4th vertebra from the urostyle. X 3.6.
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3
2
Text-figure 11.
Trachinotus goodei. Tail of 54 mm. specimen with three epurals and evidence of two pairs of uroneurals. Two interneurals and two interhaemals associated with the 5th vertebra from the urostyle. X 8.5.
specimen caught in Bermuda, KOH Cat. No. 438, length 54 mm.
Caudal Osteology.
Urostyle: The anterior part of the urostyle is cone-shaped and its margin similar to the pos- terior part of the penultimate centrum. The reduced posterior tip of the urostyle is hidden and consolidated with the base of the uroneurals. The uroneurals protect the dorsal and posterior part of the urostyle and the bases of the hypurals abut its ventral and posterior surface.
Uroneurals: These paired bones are unlike those of the other species studied in this paper. For a complete interpretation a series of younger specimens is needed. In this 54 mm. fish there are two pointed tips which form part of the hypural margin. Each represents paired lateral bones, the bases of which partly overlap the urostyle and the fifth hypural. The anterior dorsal uroneural extends from above the anterior margin of the urostyle where it is deep and wing- shaped and where bases of the epurals are inserted between its lateral bones. It extends posteriorly and dorsally and diminishes into a slender bone with a pointed distal tip. The second uroneural is similar distally but it arises immediately on the anterior part of the urostyle centrum. It overlaps the base and dorsal surface of the fifth hypural for all but the distal tip end. A broad, thin, paired bone covers part of the anterior half of the uroneurals and the fifth hypural. In our specimen of Trachinotus palometa of 119 mm. in length, only one pair of uroneurals can be found if the second pointed tip is to be interpreted as the fifth hypural. A series of young specimens is necessary in the case of both species to inter-
pret adequately the development of this part of the hypural complex.
Hypurals: There are two hypurals ventral and two dorsal to the median line. In the second large hypural there is definite evidence of a divi- sion of this bone, for there remains a suggestion of a double base with a line extending from here for half the length of the hypural. In none of the Bermuda carangids has this second hypural ap- peared as two separate bones, even in the very young of several species. This is the reason for consistently designating this particular hypural as a single bone. Its counterpart, the large hypural dorsal to the median line, has shown in several young specimens that it is formed by the fusion of two separate bones, which gives a cri- terion for calling this hypural three and four.
In this specimen hypurals three and four are distinct both anteriorly and posteriorly and only a small area in the center has fused beyond iden- tity of the two separate bones. The fifth and most dorsal hypural is similar in size at its distal extremity to the first hypural and balances this bone in its position in the hypural fan. Its length, however, is less and the median end di- minishes to a wedge-shaped tip.
Epurals: There are three epurals, which is also true of Trachinotus palometa. But in the species of this description the epurals appear more separate and individual than in Trachinotus palometa, which is a larger and older specimen. In this 54 mm. Trachinotus goodei the first or anterior epural is the largest, the second inter- mediate and the third, or posterior, the smallest. This is true of both their lengths and widths. The ventral ends are inserted between the lateral bones of the uroneurals. This is not so in the other species.
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5. Argyreiosus vomer (Linnaeus).
(Text-figures 12, 13).
Diagnostic Characters:
The caudal skeleton is conspicuously deeper and relatively shorter than any of the other species treated.
3 anterior caudal haemal spines with triangular projections on the anterior surface at mid- length.
3 short posterior neural and haemal spines stout and club-like.
Material Studied.
This description is from a study of three speci- mens presented by the American Museum of Natural History. Cat. No. 14,184 from Pom- pano, Florida; KOH Cat. No. 2321, length 18 mm. Cat. No. 12,505 from Mastic, L. I.; KOH Cat. No. 2322, length 45 mm. Cat. No. 13,583 from Rio de Janeiro; KOH Cat. No. 2323, length 140 mm.
Caudal Osteology.
Urostyle: In the adult specimen of 140 mm. in length the posterior end of the urostyle is con- solidated with the dorsal bones and cannot be distinguished.
In our young specimen of 18 mm. the urostyle extends dorsally to the hypural margin. An- teriorly, the urostyle is almost a perfect half
centrum but at the base of the second hypural it turns abruptly and extends in an oblique-dorsal direction and becomes a slender tapering rod. At the basal tip of the fifth hypural a mark ap- pears which indicates consolidation in this youth- ful stage of the urostyle. The bases of all of the hypurals are separate from the urostyle with the exception of the fifth hypural whose anterior surface is in conjunction with the urostyle.
Uroneurals: There is a single pair of uroneurals which are more distinct in the 18 mm. specimen than in the two older stages. In the smallest fish the anterior part is already enlarged and fills the area dorsal to the urostyle but the spool- shaped urostyle is distinct. In the largest speci- men the urostyle and the uroneurals have become one and there is only a suggestion of the urostyle as such. Both the anterior and the posterior portion of the uroneurals have increased in pro- portions. Distally, the uroneurals and fifth hypural have fused and there is only a suggestion of the hypural which in the 18 mm. specimen was a distinct bone.
Hypurals: In the adult specimen there are four hypural bones, two below and two above the median line. In the 18 mm. fish it is clear that the large hypural dorsal to the median line is the result of the fusion of two bones. Truly young specimens would undoubtedly show this as they have in several other species in this paper. The dorsal, or fifth hypural, is distinct in the 18 mm. specimen but in the 140 mm. fish it has be-
IHS
Text-figure 12.
Argyreiosus vomer. Tail of 140 mm. specimen. The bones of this deep-bodied fish are con- spicuously stout and the centra less elongate than in the other species. X 3.23.
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Text-figure 13.
Argyreiosus vomer. Tail of 18 mm. specimen showing the posterior end of the urostyle, the uroneurals and the fifth hypural. These are not distinct in the 140 mm. fish. There is a hint of the division of the 3rd and 4th hypurals. X 25.2.
come one with the uroneurals. The first hypural is not as massive as the corresponding bone in the adult, and there is a conspicuous large hole in the base or arch area. This is present in most of the neural and haemal bases but in the largest specimen the holes have disappeared in the three posterior processes and become smaller in the preceding arch bases.
Epurals: There are two epurals. In the 18 mm. specimen their shape in general is similar with the exception of the anterior projection on the first bone, which is a growth character. In no respect do these two bones resemble one another in the 140 mm. specimen. The anterior projection from the base of the first epural has become solid and massive and fills the area above the reduced neural process of the penultimate centrum. The rod-like form of the young specimen has disap- peared entirely. The second or posterior epural has changed very little from that of the young stage. The ventral ends of both epurals in all three stages are inserted between the lateral bones of the uroneurals.
Additional Characters Worthy of Note: As is typical of this deep bodied species, the inter- neural and interhaemal spines are massive in the adult specimen. In each there is a central shaft which is heavily ossified and has lateral projec- tions on the horizontal part. In the smallest specimen there is the beginning development of
this projection and all other parts of these bones are only slightly ossified. Several anterior caudal haemal spines are unique in development as com- pared with the other Bermuda Carangidae. The first and second are usually stout and at mid- length their surfaces abut. The three following haemal spines are also stout and have on their anterior sides heavy triangular projections. These are present in all three stages. This is illustrated in the Key (Text-fig. 5).
6. Trachurops crumenophthaltna (Bloch).
(Text-figure 14).
Diagnostic Characters:
The posterior group of two interneurals and two interhaemals associated with the fourth vertebra from the urostyle.
The haemal processes of several precaudal centra are crescent-shaped and the spines arise on the anterior half of the centra.
Material Studied.
Three specimens were used for this description and all were caught in Bermuda. Cat. No. 9,140, KOH Cat. No. 615. Cat. No. 9,140, KOH Cat. No. 614, length 115 mm. Cat. No. 25,147, KOH Cat. No. 1135, length 108 mm.
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Caudal Osteology.
Urostyle: In all specimens studied the posterior end of the urostyle is embedded in the terminal bones. The bases of the uroneurals and the hypurals surround this area. The anterior part of the urostyle is almost a perfect half centrum in shape and size. The dorsal surface is covered by the heavy uroneurals and the ventral surface by the base of the first hypural .
Uroneurals: There appears to be but a single pair of uroneurals. In our adult specimens these paired bones are massive and extend obliquely backward and dorsally from above the anterior part of the urostyle to the distal margin of the hypurals. In the anterior area a small portion of the ventral ends of the epurals are wedged be- tween the lateral bones of the uroneurals. The oblique distal part probably represents the fifth hypural fused with the uroneurals. Our material is too advanced in development to illustrate this fact, which is found in the young specimens of the closely related genera.
Hypurals: Our material shows two hypurals ventral to and two dorsal to the median line. The central bones are large and fan-shaped, which is characteristic of this family. Young specimens would undoubtedly show that the large dorsal hypural was formed by the fusion of two bones and also that the fifth hypural was separate. In these adult specimens the fifth hypural is fused with the uroneurals and not distinguishable from them. On the basis of repeated evidence in the young of several closely related genera the hy- purals are considered as five, which is seen in the Text-figure 14.
Epurals: The two epurals fill the area above the penultimate centrum and the urostyle. The long projection of the first epural extends an- teriorly above the reduced neural process of the penultimate centrum. The base is inserted be- tween the uroneurals. The second or posterior
epural is long and slender and slightly enlarged at the ventral end, which lies between the uro- neurals.
7. Chloroscotnbrus chrysurus (Linnaeus).
(Text-figures 15-18).
Diagnostic Characters:
26 or 27 interhaemals in the caudal region.
6 interhaemals between the first and second anterior caudal haemal spines.
Material Studied.
The following description is based on seven specimens taken in Haiti. Cat. No. 6,842, KOH Cat. No. 2317, lengths 100 mm. and 80 mm. Cat. No. 7,183, KOH Cat. No. 2318, lengths 15, 10, 7.5, 6.5, 6 mm.
Caudal Osteology.
Urostyle: Four stages of development were found in specimens of 6 mm., 10 mm., 15 mm., and 100 mm. in length. In the largest fish, which is fully ossified, the posterior end of the urostyle is completely hidden by the overlapping uroneurals and hypurals. As in the other Bermuda Carangidae the anterior part of the urostyle is almost a complete half centrum and is similar in proportions to the adjacent part of the preceding centrum. In the 6 mm. specimen the urostyle is a long, slender, rod-like structure which extends from the posterior margin of the penultimate centrum to the distal margin of the hypurals. Anteriorly, the proportions are similar to the adjacent part of the preceding centrum. The urostyle extends posteriorly in an oblique and dorsal direction, tapering to about one-half the depth. The ossification is delicate through- out and ends midway between the bases of the fourth and fifth hypurals. A cartilaginous rod
INS
Text-figure 14.
Trachurops crumenophthalma. Tail of 115 mm. specimen showing two interneurals and two interhaemals associated with the 4th and 5th vertebrae from the urostyle. X 11.65.
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INS
Text-figure 15. ■
Chloroscombrus chrysurus. Tail of 100 mm. specimen showing the 3rd and 4th hypurals fused and the 5th hypural united with the uroneurals. X 33.3.
extends from here and disappears in the bases of the caudal rays. In the 10 mm. specimen ossi- fication is more pronounced and the posterior dorsal end is seen at the center of the base of the fourth hypural. Anteriorly, the shape has begun to resemble that of the adult. The 15 mm. specimen shows still greater ossification and con- solidation.
Uroneurals: There is a single pair of uroneurals, which in the adult is indicated only at the distal end. These bones have become fused with the
fifth hypural in the largest specimen. The three younger stages show clearly the development of the uroneurals. In the 6 mm. specimen this paired bone extends dorsally above the urostyle from the region of the second hypural to the margin of the hypurals. It is long and slender and the anterior end is slightly larger than the posterior tip. It is of importance to note the relation of this bone to the others and its inde- pendent position, which is found only in the very young stages.
Chloroscombrus chrysurus. Tail of 6 mm. specimen which is partly ossified. There are no interneurals or interhaemals or epurals. The 3rd, 4th and 5th hypurals and the uroneurals are separate bones. The urostyle extends into the hypural margin. X 104.
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Text-figure 17.
Chloroscombrus chrysurus. Tail of 10 mm. specimen showing increased ossification. The centra are spool-shaped and the epurals, uroneurals and base of the interneural and interhaemal spines have appeared. The 3rd and 4th hypurals have begun to fuse and the uroneurals abut the fifth hypural. X 83.
In the 10 mm. specimen the uroneurals have increased anteriorly both in depth and length and almost reach the anterior margin of the uro- style. The shape of this end has changed from a blunt rounded tip to a deeper indented form. The posterior part is reduced and the distal end appears in conjunction with almost half the proximal length of the fifth hypural. In this region the uroneurals have grown over the uro- style. The anterior part is still separate from the urostyle.
In the 15 mm. specimen the uroneurals re- semble the structure of the adult more than the 10 mm. specimen, and the shape and proportions are similar. The base of the uroneurals has fused with the dorsal surface of the urostyle and in only one place is there any indication of the youthful stage where all the under part of this bone was entirely separate. There still remains two perforations or unossified areas. The ante- rior part of the uroneurals abut the reduced neural process of the penultimate centrum and extend dorsally almost to the distal margin of the fifth hypural. In this stage the uroneurals have be- come entirely consolidated with the dorsal surface of this fifth hypural.
Hypurals: In the adult 100 mm. specimen there are two hypurals below and two above the median line. The first and fifth hypurals are the same size distally and flank the ventral and dorsal
part of the hypural fan. Two large hypurals form the central part of the hypural complex ; one below and one above the median line. From a study of the young specimens it is certain that the large dorsal hypural is formed by the fusion of two bones and that the fifth hypural has fused with the uroneurals.
In the 6 mm. specimen, which is the youngest stage available for study of the Bermuda Caran- gidae, there are five distinct hypural bones. The first, or anterior bone, is long and slender and slightly enlarged at the median base. This base, which is the haemal arch, develops rapidly in the 10 mm. and 15 mm. stages. In the smaller fish a square, wing-like growth projects ante- riorly and abuts the haemal process of the pre- ceding centrum and there is a large hole or unossified area in the center of this growth. In this stage the lateral ridge, for the muscle attach- ment, is a small triangular projection from the base and overlaps slightly the base of the second hypural. In the 10 mm. specimen this ridge has more than doubled in size and proportion.
The first hypural of the 15 mm. specimen resembles the corresponding bone of the adult fish with the exception of the density of ossifica- tion, and extent of development of the muscle attachment process, and proximity to the ventral surface of the urostyle. There is still considerable space between the haemal arch and the urostyle,
42
Zoologica: New York Zoological Society
[XXVI: 8
which entirely disappears in the adult specimen. This is also true of the preceding haemal arches.
The second hypural changes less in shape and proportions than any of the other hypural bones. In the 6 mm. specimen the base is divided into two by a long oval slit which extends for about one-quarter the length of the bone. In the 10 mm. specimen the two bases have fused but a small oval hole remains. In the 15 mm. fish there is no indication of either the two bases or the slit of the younger stages. The third and
form part of the caudal margin. In the 15 mm. specimen the degree of ossification is identical with the other caudal bones. The shape of both epurals is similar to that of the adult, and the median ends are ir erted between the uroneurals, which is also an adult character.
Additional Characters Worthy of Note: The illustrations show the increase in ossification with age and also the change in shape and pro- portions of all of the caudal bones. In the 6 mm. specimen there is no evidence of epurals, inter-
Text-figure 18.
Chloroscombrus chrysurus. Tail of 15 mm. specimen. The posterior end of the urostyle is reduced and the distal portion of the uroneurals flank the side of the 5th hypural. In the 100 mm. specimen these two bones have fused. X 42.
fourth hypurals are separate bones in the young- est stage and in the 10 mm. specimen their distal margin has fused and the space between become less. The 15 mm. fish still lias two bases which represent the two separate bones of the younger stage but the slit between has diminished by more than half its former length. In the 100 mm. specimen there is no trace of a slit or double base. The fifth hypural appears as a very small wedge-shaped bone between the distal end of the urostyle and the fourth hypural . Its growth and development from this stage to the adult is remarkable and without several very young specimens this hypural would not be identified as an hypural bone. In the youngest stage this bone is entirely separate from the surrounding structures. In the 10 mm. fish the bone has in- creased in length and depth and about one-lialf of its anterior length abuts the uroneurals on the dorsal surface. In the 15 mm. specimen the length is greatly increased and all but a small part of the dorsal end is in conjunction with the uroneurals. The adult specimen of 100 mm. shows that the fifth hypural and the uroneurals have fused and all that remains of their separate identity is a light line at the distal extremity.
Epurals: There are two epurals in this species. Neither of these bones can be found in the 6 mm. fish. In the 10 mm. specimen these epurals appear with delicate ossification and as long slender bones. The anterior epural is longer and broader than the second one and has the be- ginning of the anterior projection near the median end. Both bones are free and their distal tips
neurals and interhaemals. The centra are rectangular in shape with considerable distance between their margins. In the 10 mm. specimen the spool-shape of the centra begins to change and to resemble the adult. The epurals are lightly ossified and also the interneurals and interhaemals. The zygapophyses are present on the dorsal and ventral surfaces of the centra. With the consolidation from a long rectangular structure to a shorter spool-shaped centra the neural and haemal processes appear to shift from their youthful anterior position to a central position. The three reduced posterior neural and haemal spines of the adult are simple and unmodified in the 6 mm. and 10 mm. specimens.
8. Caranx ruber (Bloch).
(Text-figure 19).
9. Caranx bartholomaei Cuvier & Valenciennes
Diagnostic Characters (both species) :
Total of 24 interhaemals in the caudal region.
Total of 22 interneurals in the caudal region.
4 interhaemals between the first and second anterior caudal haemal spines.
3 interneurals and 3 interhaemals in posterior group in three specimens. The oblique part more slender than in the two following species.
Minor species differences cited in Key and in text.
1941]
Hollister: Caudal Skeleton of Bermuda Shallow Water Fishes
43
Material Studied.
Caranx ruber; one specimen taken in Haiti. Cat. No. 7,016, KOH Cat. No. 2320, length 160 mm.
Caranx bartholomaei; two specimens caught in Bermuda. Cat. No. 25,057, KOH Cat. No. 1074, length 50 mm. Cat. No. 25,065, KOH Cat. No. 1073, length 52 mm.
Caudal Osteology.
Urostyle: The reduced terminal end is hidden in both species by the heavy uroneurals on the dorsal and the base of the hypurals on the ventral surface. No small specimens are available to show the development. The anterior part is cone-shaped and of the same proportions as the posterior half of the penultimate centrum. The dorsal surface is covered by the uroneurals and the ventral by the first hypural in Caranx ruber (Text-fig. 19). In Caranx bartholomaei, which is one-third the length, the base of the first hypural is still separate from the ventral surface of the urostyle.
Uroneurals: In the 50 mm. specimen of Caranx bartholomaei there is indication of one pair of uroneurals. At the distal end the line of junction between the uroneurals and the fifth hypural still remains. There is no evidence of this in the 160 mm. specimen of Caranx ruber. In this species the two bones have fused.
Hypurals: In both species there are two hy- purals which are ventral to and dorsal to the median line. Their positions and proportions are similar in the corresponding bones. Because of facts presented by several young stages in closely related genera in this family, the hypural bones of these species are numbered 1 to 5 in the illustration.
Epurals: There are two epurals in both species and the corresponding bones are similar in shape
and position. In the distal dorsal portion of the smaller Caranx bartholomaei the epurals are more slender. This has been found to be an age character in other genera.
Additional Characters Worthy of Note: In Caranx ruber the posterior neural zygapophyses have hook-like projections on the dorsal surface. This is shown in the anterior vertebra in the illustration. The development is especially prominent in the central caudal area. In Caranx bartholomaei the dorsal surfaces of the corre- sponding zygapophyses are smooth. There is also a difference in the development of the anterior neural zygapophyses of the two species. In Caranx ruber the surfaces are jagged and notched, especially in the central caudal area, but this is not true in Caranx bartholomaei. In a detailed study of the two species many minor differences such as these distinguish each as a different species.
10. Caranx crysos (Mitchill).
11. Caranx latus Agassiz.
(Text-figure 20).
Diagnostic Characters (both species) :
Total of 17 to 20 interhaemals in the caudal region.
Total of 15 to 18 interneurals in the caudal region.
3 interhaemals between the first and second anterior caudal haemal spines.
2 interneurals and 2 or 3 interhaemals in the posterior group in the five specimens studied. The oblique part broader than in the two preceding species.
Minor species differences are cited in the Key and in the text.
Text-figure 19.
Caranx ruber. Tail of 160 mm. specimen. This figure represents both this species and Caranx bartholomaei which in gross structure are similar. X 2.74.
44
Zoologica: New York Zoological Society [XXVI: 8
INS
Text-figure 20.
Caranx latus. Tail of 87 mm. specimen. This figure represents both this species and Caranx crysos, the gross structure being similar. X 15.87.
Material Studied.
Caranx crysos; one specimen taken in Haiti. KOH Cat. No. 2319, length 130 mm.
Caranx latus; four specimens caught in Bermu- da. KOH Cat. No. 1070, length 44 mm. KOH Cat. No. 412, length 63 mm. KOH Cat. No. 649, length 80 mm. KOH Cat. No. 1040, length 87 mm.
Caudal Osteology.
Urostyle: The anterior part of the urostyle in both species is cone-shaped and almost identical in shape with the posterior half of the preceding centrum. The dorsal surface is fused with the bases of the uroneurals and the ventral surface with the base of the first hypural. The posterior end cannot be distinguished in specimens as old as those in this collection. Text-figure 20 repre- sents both species.
Uroneurals: In the 87 mm. specimen of Caranx latus one pair of uroneurals is found where it has fused during growth with the fifth hypural. In Caranx crysos, which is 130 mm. in length, there is no evidence left and the fifth hypural and uroneurals appear as one structure.
Hypurals: In both species there are two hy- purals below and two above the median line. They are similar in proportions and arrangement to the other species of Caranx. None of these specimens are young enough to show the develop- ment and eventual fusion of the hypurals but the figure is numbered to show the position of five hypurals which the young of closely related genera have demonstrated.
Epurals: There are two epurals, as in all but one genus of Carangidae. In the distal portion of the smaller Caranx latus these bones are more slender than those of Caranx crysos. This de- velopment is correlated with age in other genera.
Additional Characters Worthy of Note: In Caranx crysos there are 20 interhaemals in the caudal region and 18 interneurals. There are fewer in Caranx latus, which has 17 interhaemals and 15 or 16 interneurals in the caudal region. The shapes and proportions of the zygapophyses differ in the two species, also the presence and absence of neural and haemal arch perforations. In a detailed study of the minor differences in both species these can be distinguished as two separate species.
Summary.
The following facts correlate the salient simi- larities found in the study of Bermuda Caran- gidae.
Vertebral count: 10 trunk plus 14 caudal in all species but Caranx crysos and Decapterus punc- tatus. These have 10 trunk and 15 caudal. In both, only one specimen was available for the count.
Caudal fin count : There is only slight variation among the species. The illustration of Tra- chinotus palometa (Text-fig. 10) shows the ar- rangement. It is usually 6 raylets plus 11 rays dorsal; 6 raylets plus 9 rays ventral, making a total of 17 dorsal, plus 15 ventral.
Epurals: There are two epurals in all but the genus Trachinolus, which has three.
Hypurals: In the adults of all species there are four hypurals; two below and two above the median line. The two central bones are large and fan-shaped. The dorsal or fifth hypural is fused with the uroneurals in all adults. In the young stages it is separate. In young stages the large dorsal hypural is found to be formed by the fusion of two separate bones. There remains a hint in several of the young of a one-time division of the large ventral or second hypural. This is not complete in any specimens of this
1941]
Hollister: Caudal Skeleton of Bermuda Shalloiv Water Fishes
45
family. In all Bermuda Isospondyli and Iniomi there are at least three hypurals below the median line.
Uroneurals: In all species but Trachinotus goodei there is a single pair of uroneurals. Here there is a suggestion of a second pair, but young specimens are necessary to ascertain this fact.
Elongate spines in caudal complex: In the adult of all species one long neural spine and two long stout haemal spines form the anterior part of the caudal complex.
Anterior caudal haemals: Decapterus is the only genus in this series which has the bases of
the first few anterior caudal haemals crescent- shaped and situated on the anterior half of the centra. The typical shape is triangular.
Pre-caudal haemals : Decapterus and Trachurops have crescent-shaped precaudal haemal bases which are situated on the anterior half of the centra.
Specialized neural process: Adult specimens of all species of Bermuda Carangidae have a reduced neural process on the penultimate centrum. The long anterior projection from the first epural extends into the area above this process.
ISHES.
GROUP I
3 posterior neural and mal caudal spines spicuously short or st 2 epurals.
c
A
R
A
N
G
I
D
A
Text-figure 1.
Caranx ruber
Posterior neural zygapophyses with hook- like projections on the dorsal surfaces, especially in the central caudal area.
Anterior neural zygapophyses with notched dorsal surfaces especially in the central caudal region.
-Group A
interhaemals and 20 to 22 interneurals in caudal region.
linterhaemals between the first and second ‘anterior caudal haemal spines.
Caranx bartholomaei
No hook-like projections on dorsal surfaces of posterior neural zygapophyses.
Anterior neural zygapophyses with smooth dorsal surfaces.
GROUP II
No conspicuously short terior neural and h spines.
3 epurals.
Caranx crysos
20 interhaemals and 18 interneurals in cau- dal region.
-Group B
to 20 interhaemals and 15 to 18 inter- neurals in caudal region, interhaemals between the first and second anterior caudal spines.
Caranx latus
17 interhaemals and 15 or 16 interneurals in caudal region.
KEY TO CAUDAL SKELETON OF BERMUDA SHALLOW WATER CARANGID FISHES.
(Text-figs. 1-6).
c
A
R
A
N
G
I
D
A
E
GROUP I
3 posterior neural and hae- mal caudal spines con- spicuously short or stout. 2 epurals.
Text-figure 1.
Decaptcrus macarellus
1 intemeural and 1 interhaemal arising over the 4th vertebra anterior to the urostyle. The horizontal part about one and a half times longer than the anterior oblique part.
Sub-Group A
Horizontal length of posterior inter- neural and inter- haemal conspicu- ously longer than the preceding spines.
1st anterior caudal haemal arch cres- cent-shaped and on anterior half of centrum.
Text-figure 3.
Decapterus punctatus
2 intemeurals and 2 interhaemals arising over the 4th vertebra anterior to the uro- style.
The horizontal part only a little longer than the oblique part.
Sub-Group B
Horizontal length of posterior inter- neural and inter- haemal not con- spicuously long and the general shape the same as the spines im- mediately preced- ing.
1st anterior caudal haemal arch not crescent -shaped and on entire centrum.
Division I Argyreiosus vomer
3 anterior caudal hae- mal spines with tri- angular projections at mid-length.
Posterior vertebrae rel- atively shorter and more massive than in Division II.
Sub-Division A Trachurops crumenophthalma
Posterior group of intemeurals and inter- haemals associated with 4th vertebra from the urostyle.
Precaudal haemal process crescent-shaped and on anterior half of centrum.
Division II
No triangular projec- tions on anterior caudal haemals.
Posterior vertebrae rel- atively longer and more slender than in Division I.
Group I
Chloroscombrus chrysurus
26 or 27 interhaemals.
6 interhaemals between the first and second anterior caudal hae- mal spines.
Sub-Division B
Posterior group of intemeurals and inter- haemals associated with 5th vertebra from the urostyle.
Precaudal haemal process triangular-shaped and covers all of centrum.
GROUP II
Trachinotus palometa
No conspicuously short or stout pos- terior neural and haemal caudal spines.
3 epurals.
1 intemeural and interhaemal spine over the 4th vertebra from the urostyle.
17 intemeurals in caudal region.
Trachinotus goodei
2 intemeural and interhaemal spines over the 5th vertebra from the urostyle.
15 intemeurals in caudal region.
Group II Caranx
Less than 26 interhaemals.
3 or 4 interhaemals between the first and second anterior caudal haemal spines.
Caranx ruber
Posterior neural zygapophyses with hook- like projections on the dorsal surfaces, especially in the central caudal area.
Anterior neural zygapophyses with notched dorsal surfaces especially in the central caudal region.
Sub-Group A
24 interhaemals and 20 to 22 intemeurals in caudal region.
4 interhaemals between the first and second anterior caudal haemal spines.
Caranx bartholomaei
No hook-like projections on dorsal surfaces of posterior neural zygapophyses.
Anterior neural zygapophyses with smooth dorsal surfaces.
Caranx crysos
20 interhaemals and 18 intemeurals in cau- dal region.
Sub-Group B
17 to 20 interhaemals and 15 to 18 inter- neurals in caudal region.
3 interhaemals between the first and second anterior caudal spines.
Caranx latus
17 interhaemals and 15 or 16 intemeurals in caudal region.
Text-figure 2.
1941]
Crandall: Description of an Egg of the Long-tailed Bird of Paradise
47
9.
Description of an Egg of the Long-tailed Bird of Paradise.
Lee S. Crandall.
Plate I.
On June 16, 1937, a pair of Long-tailed Birds of Paradise, Epimachus meyeri meyeri Finsch, collected by F. Shaw Mayer “near the head of the Waria,” were received at the Zoological Park. During following years, frequent displays of the male were noted but as this is a common practice in the group and there was no evidence of nesting activity, we expected no further re- sult. However, the female was noticed in coma- tose condition on the afternoon of February 28, 1941, and on examination was found to be egg- bound. She responded well to treatment and the egg was safely laid about two hours later.
Since the egg of this species appears to be undescribed, the following notes are given.
The egg measures 44.25 X 28.5 mm. Its weight was 18.9 grams or approximately .62 ounces. The ground color is buff (close to Cart- ridge Buff of Ridgway). It is heavily blotched and streaked at the large end, the markings decreasing toward the small end, which is almost clear. The under markings are grayish (close to Pale Mouse Gray of Ridgway) while those on the surface are reddish-brown (near Russet of Ridgway) .
48
Zoologica: New York Zoological Society
[XXVI: 9
EXPLANATION OF THE PLATE.
Plate I.
Fig. 1. Egg of Epimachus meyeri meyeri Finsch. Actual size.
CRANDALL.
PLATE I
FIG. 1.
DESCRIPTION OF AN EGG OF THE LONG-T A I LED BIRD OF PARADISE
1941]
Breder cfc Krumhols: On the Uterine Young of Dasyatis sahinus
49
10.
On the Uterine Young of Dasyatis sabinus (Le Sueur) and Dasyatis hastatus (De Kay).
C. M. Breder, Jr. & Louis A. Krumholz
New York Aquarium and University of Illinois.
(Text-figures 1 & 2).
The small sting ray, Dasyatis ( Amphotistius ) sabinus (Le Sueur) is abundant along the west coast of Florida in the vicinity of the field station of the New York Aquarium on Palmetto Key. Here mature gravid females may be found at sizes not greatly exceeding those of the relatively new- born young of the much larger Dasyatis hastatus (De Kay).
Apparently there is a dearth of material in the literature concerning the size of gravid fe- males, the number of young per individual and the sex ratios of the young. The catches of the stop-netters operating in Bull’s Bay (Cara Pelau on the northern side of Charlotte Harbor on the U. S. coastal charts) provided the data of the accompanying tables, except as noted. The 1939 material was collected by M. B. Bishop of Peabody Museum, Yale University.
The sizes of some of the gravid females of D. sabinus did not greatly exceed those of the new-born young of D. hastatus taken on June 29. These latter ranged from 160 to 176 mm. in length, while one not quite mature male of the former was only 174 mm. long. Three full-term embryos taken from one female D. sabinus varied in length from 99 to 100 mm.
It can be seen that there is a steady increase in size of the embryos of D. sabinus from a mean of 35.8 mm. on June 19 to a mean of 99.6 on July 11. Also, there was no overlapping of the means and extremes on the various dates. If this can be taken to indicate the growth rate, on so few data, it is remarkably rapid.
If the length of the disc (from the tip of the snout to the posterior border of the disc) is com- pared with the width, it is seen that the two dimensions are nearly equal. Moreover, this relationship holds from the smallest embryos obtained through to the adult (Text-fig. 1), clearly showing it to be a straight line relation- ship. D. hastatus, which is a little wider than long, has a similar straight line relationship, but is not so close to a 45° angle. This is clearly a
most unusually constant growth rate for which there is no superficial explanation at this time. It is not of importance in intra-uterine life nor can it be in post-uterine life when the extremely different relationships of various other species of rays, otherwise much alike, are taken into con- sideration. The growth relationship of these is so constant that it might be simulated to flap- jack batter spreading out on a pan. Except in the early embryos, this relationship is sufficient to separate these two species which so closely resemble each other. Text-fig. 1 also indicates the relative sizes of the adults and also the size of the young at delivery.
A full-term young of each species is illustrated in Text-fig. 2 for purposes of comparison. The general shape and the presence of the keel on the tail of D. hastatus make separation simple. The folding in of the tail, at its origin from the body, in D. hastatus as compared with the flaring out in D. sabinus is another characteristic.
It was not always possible to identify each young fish with its mother, because in capture some of the females aborted, resulting in a mix- ture of mothers and young. These young, even though the yolk sac was still hanging outside the body, were able to swim around actively when placed in an aquarium. To avoid possible mistakes and confusion, the young have been considered in groups as taken. The material did show a variation in numbers of young from one to three in D. sabinus and from two to five for D. hastatus. On June 19, 1940, there was one gravid D. sabinus which carried but one embryo. This embryo was nearly twice the size of the others taken on the same date. However, on June 28, 1940, we took another female which carried but one embryo and this was very nearly the same size as others taken on the following day.
The sex ratios of all the embryos of D. sabinus combined (25) showed 56% to be male. How- ever, one mother carried three female embryos.
50
Zoologica: New York Zoological Society
Table I.
[XXVI: 10
Size and Sex of Dasyatis Embryos.
Dasyatis sabinus.
|
Disc in |
mm. |
Female |
Male |
All |
||||||
|
Date |
Length Width |
Sex |
Max. |
Mean |
Min. |
Max. |
Mean |
Min. |
Mean |
|
|
4/9/39 |
55 |
55 |
m) |
|||||||
|
Captiva Pass |
49 |
48 |
f) |
49 |
49 |
49 |
55 |
55 |
55 |
52 |
|
6/19/40 |
30 |
29 |
f |
|||||||
|
33 |
32 |
f |
||||||||
|
33 |
30 |
f |
||||||||
|
50 |
53 |
f |
||||||||
|
33 |
30 |
m |
50 |
38.5 |
30 |
33 |
33 |
33 |
35.8 |
|
|
6/28/40 |
78 |
81 |
m |
— |
— |
■ — ■ |
78 |
78 |
78 |
78 |
|
6/29/40 |
71 |
72 |
f |
|||||||
|
74 |
77 |
f |
||||||||
|
82 |
81 |
f |
||||||||
|
83 |
87 |
f |
||||||||
|
68 |
69 |
m |
||||||||
|
69 |
67 |
m |
||||||||
|
70 |
71 |
m |
||||||||
|
70 |
73 |
m |
||||||||
|
70 |
74 |
m |
||||||||
|
71 |
72 |
m |
||||||||
|
71 |
* 74 |
m |
||||||||
|
74 |
75 |
m |
||||||||
|
75 |
76 |
m |
||||||||
|
77 |
79 |
m |
||||||||
|
79 |
81 |
m |
||||||||
|
79 |
81 |
m |
83 |
77.7 |
71 |
79 |
72.9 |
68 |
75.2 |
|
|
7/11/40 |
99 |
99 |
f |
|||||||
|
East side of Useppa Island |
99 |
99 |
f |
|||||||
|
100 |
101 |
f |
100 |
99.6 |
99 |
— |
— |
— |
99.6 |
|
|
Dasyatis hastatus. |
||||||||||
|
4/9/39 |
76 |
83 |
f |
|||||||
|
Captiva Pass |
75 |
83 |
f |
76 |
75.5 |
75 |
75.5 |
|||
|
4/10/39 |
97 |
102 |
m |
|||||||
|
Captiva Pass |
95 |
101 |
f |
97 |
97 |
97 |
95 |
95 |
95 |
96 |
|
6/24/40 |
85 |
87 |
f |
|||||||
|
82 |
88 |
f |
||||||||
|
86 |
87 |
m |
||||||||
|
85 |
89 |
m |
82 |
82 |
82 |
85 |
85 |
85 |
83.5 |
|
|
6/29/40 |
172 |
193 |
f |
|||||||
|
176 |
197 |
f |
||||||||
|
160 |
189 |
m |
||||||||
|
170 |
192 |
in |
||||||||
|
168 |
195 |
m |
176 |
174 |
172 |
170 |
166 |
160 |
169.2 |
The relatively few young of D. hastatus (9) showed 55.5% to be male. Since there were in all 12 gravid D. sabinus and 25 embryos, they averaged 2.08 per mother. The four D. hastatus
females averaged 3.25 per mother. These latter are much larger in relation to the size of the young they liberate; the difference in number seems to be purely mechanical.
1941]
51
Date
6/19/40
Length to notch
6/28/40
6/30/40
7/11/40
6/24/40
6/29/40
Unlabeled
Breder & Krumholz: On the Uterine Young of Dasyatis sahinus
Table II.
Size and Sex of Dasyatis Adults.
Dasyatis sabinus.
|
Length |
Width |
Sex |
||
|
(201 |
— |
f |
not gravid |
|
|
202 |
— |
f |
not gravid |
|
|
214 |
— |
f |
not gravid |
|
|
222 223 |
|
f f |
gravid gravid |
■5 embryos |
|
244 |
— |
f |
gravid |
|
|
247 |
— • |
f |
not gravid |
|
|
262 |
— |
f |
not gravid |
|
|
190 |
— |
m |
||
|
190 |
— |
m |
||
|
199 |
— |
m |
||
|
213 |
— |
m |
||
|
218 |
— |
m |
||
|
(234 |
— |
m |
||
|
238 |
245 |
f |
gravid |
1 embryo |
|
174 |
179 |
m |
imm. |
|
|
— |
235 |
f |
gravid |
|
|
■ — |
241 |
f |
gravid |
|
|
243 |
245 |
f |
gravid |
|
|
— |
254 |
f |
gravid |
16 embryos |
|
— |
260 |
f |
gravid |
|
|
— |
286 |
f |
gravid |
|
|
— |
286 |
f |
gravid |
|
|
220 |
224 |
m |
||
|
— |
235 |
m |
||
|
291 |
297 |
f |
gravid |
3 full term embryos (all females) |
|
Dasyatis hastatus. |
||||
|
851 |
984 |
f |
gravid |
4 embryos |
|
— Circa 914 |
f |
gravid |
5 embryos |
|
|
272 |
310 |
f |
not gravid |
LENGTH OF DISC. MILLIMETERS
52
Zoologica: New York Zoological Society
[XXVI: 10
Text-figure 1.
Comparison of length and width of disc in pre-natal and post-natal Dasyatis based on data in Tables I and II.
1941]
Breder & Krumholz: On the Uterine Young of Dasyatis sabinus
53
Text-figure 2.
Dorsal view of full-term embryos of two species of Dasyatis.
1941]
Shlaifer: Respiratory Behavior in Small Tarpon
11.
Additional Social and Physiological Aspects of Respiratory Behavior in Small Tarpon.
Arthur Shlaifer
New York Aquarium & U. S. Fish & Wildlife Service, Woods Hole, Mass.
Introduction.
Tarpon, Tarpon atlanticus (Cuv. & Val.), whose swimbladders contain considerable al- veolar tissue, periodically rise to the surface to breathe atmospheric oxygen despite their ex- tensive gill surfaces and the relatively high oxygen content of the waters they normally inhabit.
The work reported here represents a continu- ation of the program of investigation with small tarpon begun by Shlaifer & Breder (1940). In this earlier work, which, incidentally, is the first experimental report on this fish, it was found, among other things, that the surface rise of a tarpon to gulp air may induce similar rises in others in a group. For instance, in a group of four in a 50-liter aquarium, in 70% of the cases a rise by one tarpon would induce a rise in one or more companions. It was shown that “coinci- dence” was not involved as a disturbing factor and that, apparently, a tarpon had to be in a “physiologically receptive” state by virtue of a depleted oxygen supply before such imitative rises could be induced. In preliminary experi- ments, some success was attained in inducing rises by means of a silver-painted carved wooden tarpon model manipulated so as to simulate the normal rise of this fish. In the present report “model” experiments were considerably ex- tended.
Shlaifer & Breder (1940) found that while the locomotor activity of tarpon did not change when the oxygen content of the water was raised from 2.50 cc. per liter to 5.60 cc., the rate of surface (respiratory) rises to gulp air decreased markedly. As a continuation of this line of in- vestigation, experiments were performed to de- termine the effect of waters of distinctly low oxygen content on locomotor activity and surface rises; also, survival time was determined for tarpon whose access to the surface and hence to atmospheric oxygen was cut off.
The writer wishes to express his appreciation to Dr. C. M. Breder, Jr., of the New York Aquarium for the experimental animals and to the U. S. Fish and Wildlife Service at whose
Woods Hole laboratories the experiments were performed.
The Induction of Imitative Respiratory Rises.
As discussed above, it has been found (Shlaifer & Breder, 1940) that imitative surface rises in small tarpon may be induced by a ma- nipulated wooden model as well as by other tarpon. Models have been used with and with- out success in various lines of investigation on behavior in fishes. Thus, Lissmann (1932) found that the characteristic fighting reaction of the Siamese fighting fish, Betta splendens, is elicited by plasticine models or paintings of the fish. Noble (1934) working with the dwarf sunfish, Eupomotis gibbosus, and Breder (1936) with the sunfish, Lepomis auritus, found that males would attempt to mate with a variety of objects irrespective of their general appearance provided they were manipulated so as to re- semble somewhat the actions of a female ready to spawn. On the other hand, Spooner (1931) found that the bass, Morone labrax, was not attracted by various rough models of itself. Breder & Coates (1935), investigating the sex recognition of the guppy, Lebistcs reticulatus, found that no reaction was given to carefully made models of female Lebistes with or without movement. Finally, Shlaifer (1940) failed to obtain a reaction to sunfish models by goldfishes.
Granted that a properly manipulated wooden model may induce imitative rises in tarpon, will other objects properly manipulated but differing appreciably from a tarpon in shape and color also induce rises and if so to what extent? Will a tarpon model or other objects be effective if manipulated so as to rise in a manner appreciably different from the normal one? In an attempt to answer these questions the experiments de- scribed below were performed.
Materials and methods. The animals used in these and other experiments described in this paper were 10-12 cm., presumably young, speci- mens sent from the collection at the New York
56
Zoologica: New York Zoological Society
Aquarium but originally obtained along the Florida coast. They were kept in sea water and were fed chopped herring three times a week. The experimental group in the model tests was composed of six tarpon placed in 40 liters of standing sea water in a 48-liter rectangular as- sembled aquarium with transparent glass sides, whose dimensions were 55 cm. by 35 cm. and 25 cm. deep. The water temperature range was 19-22 degrees C. and the average oxygen content was 2.50 cc. per liter.
Four different types of object, all 10 cm. in length, were used as “models” in the attempts to induce imitative rises in the experimental animals. These were: 1. A silver-painted carved wooden model of a tarpon having no fins or mouth but possessing an “eye” fashioned out of a thumbtack. 2. A white spatula. 3. A piece of red rubber tubing 1 cm. in diameter. 4. A solid glass rod 4 mm. in diameter. Two pieces of string were attached to these objects at opposite ends. The object to be tested was suspended horizontally in the experimental aquarium con- taining the six tarpon, next to the long side of the aquarium nearest the observer, at a distance of 3.5 cm. from the bottom, the level at which the tarpon in that situation generally swam. The observer, seated about two feet away from the aquarium and facing one long side, manipu- lated the object by means of the two strings. The normal air-gulping rise of a tarpon is a rapid movement lasting a little less than a second from the start of the rise to the return to the normal position. Usually the animal rises to the surface almost vertically. In A of Table I this type of rise was simulated by properly manipulating the objects. In B of Table I the object or model was manipulated so as to produce a distinctly “ab- normal” rise. The object was raised to the sur- face parallel with it rather than at a right angle and the rise from beginning to end lasted two seconds. The data in Table I are listed in terms of successful attempts to induce rises in the tarpon by means of the manipulated objects. Each time the object is raised to the surface is considered an “attempt.” The attempt is con- sidered successful if within one second or less following the start of the rise of the model one or more tarpon rise to the surface. Rises by the fishes two or three seconds after the object had risen might also have been imitative delayed reactions but were not considered. Indeed, such rises very rarely occurred. Either the fish would respond immediately or it would not rise for a minute or more. No effort was made to differ- entiate between induced imitative rises that in- volved varying numbers of tarpon. In fact, such differentiation is very difficult if not impossible since, except in rare cases in which two or more individuals arose at exactly the same tune, one cannot determine whether the rise of the tarpon following very closely that of the first animal to rise is a response to the object or to the first tarpon.
Observations were made within a ten-minute experimental period. Every second, fourth,
[XXVI: 11
sixth, eighth, and tenth minute on the minute the model was raised to the surface and the reaction noted. As a control, every first, third, fifth, seventh, and ninth minute on the minute an observation was made for rises of the tarpon without the manipulation of an object. Each observation, control and experimental, at the two minute interval lasted only one second. In general, observations were made during two con- secutive hours, or 12 experimental periods each day.
Results. The data in A of Table I indicate that all four types of objects induce imitative rises whose statistical significance compared with the controls is very high. The average rise of a tarpon in the experimental aquarium was twice in ten minutes. In a group of six animals there would be at most twelve seconds of rising in 10 X 60 or 600 seconds; thus, according to the laws of chance, rises of tarpon directly following those of models cannot very well be considered coinci- dental. It is seen that, of the four objects used, the wooden tarpon model is significantly most ef- fective and the red rubber tubing is second. The degree of success in inducing imitative rises is, however, sharply limited by the physiological state of the animal. As Shlaifer& Breder (1940) demonstrated, a tarpon will not respond imita- tively to the rise of another object, even if it be an- other normal tarpon, unless, by virtue of the fact that the oxygen obtained at the last gulp is dis- tinctly depleted, it is in a “physiologically recep- tive ” state which permits a rising response. The induction of an imitative rise, then, depends on the reaching of a respiratory threshold by the reacting animal. This explains why even the wooden tarpon model enjoys only 48.3% success in inducing rises. The experimental animals may rise either singly or imitatively in groups just before the model is raised to the surface. If so, even raising the object consecutively three times or more will produce no response.
The data in B of Table I demonstrate that objects manipulated so as to rise in an “abnor- mal” way induce few i mitative rises . Comparison with the controls indicates no statistical signifi- cance .
Surface Rises in Blinded Tarpon.
That the induction of imitative rises in small tarpon is a visual affair was demonstrated by Shlaifer & Breder (1940). It was found that the rise of a tarpon on one side of a transparent glass plate bisecting an aquarium could induce a rise in others on the opposite side.
Carrying this a step further, four tarpon were blinded by piercing the cornea. Blindness was ascertained by appropriate tests. Several days were allowed for recovery from the operation. Subsequently, the animals were grouped together in 40 liters of standing sea water (oxygen con- tent— 2.50 cc. per liter) in a 48-liter aquarium whose dimensions have been listed above.
In the course of several hours of observation no imitative rises occurred. The tarpon rose
57
1941] Shlaifer: Respiratory Behavior in Small Tarpon
Table I.
The Induction of Imitative Surface Rises in Small Tarpon by Various Objects.
|
A. Object manipulated so as to simulate |
a normal surface rise. |
||||
|
I Silver |
II |
Ill |
IV |
V |
|
|
Type of Model |
Wooden |
White |
Red Rubber |
Glass |
Control2 |
|
Tarpon |
Spatula |
Tubing |
Rod |
||
|
Total Number of Attempts1 |
176 |
181 |
176 |
170 |
703 |
|
Number of Successful Attempts |
85 |
52 |
62 |
35 |
12 |
|
% of Successful Attempts |
48.3 |
28.7 |
35.2 |
20.6 |
1.7 |
1 Object is raised to surface for one second every two minutes in a 10-minute observation period in an attempt to induce a rise in the experimental tarpon in the aquarium.
2 Observation made for one second every two minutes in the 10-minute period for rises by tarpon without manipu- lation of objects.
Statistical significances (number of successful attempts).*
I vs. II — .0096 I vs. Ill — .0210 I vs. IV — .0013 II vs. Ill — .4370
II vs. IV— .2898 III vs. IV— .0210 I, II, III, IV vs. V— .0000
* Upper limit of statistical significance is set at 0.05. This is three times the probable error. 0.01 indicates good significance while a value of 0.100 or more indicates little significance. (“Student,” 1925.)
B. Manipulation of object does not simulate a normal rise.f
Type of Model
Total Number of Attempts1 Number of Successful Attempts % of Successful Attempts
I Silver Wooden Tarpon 65 5
7.7
II III
White Red Rubber Spatula Tubing 65 65
5 1
7.7 1.5
t Object is raised to surface slowly and parallel with the surface.
1 See 1 above.
2 See 2 above.
Statistical significances (number of successful attempts).
I vs. II — None
II vs. Ill— .3834
I vs. Ill — .3342 II vs. IV— .4370
I vs. IV — .4954 III vs. IV — .5580
I vs. V— .1832 III vs. V— .5580
IV
Glass
Rod
65
2
3.1
V
Control2
260
6
2.3
II vs. V — .2146 IV vs. V— .5580
I (A) vs. I (B)— .0000 II (A) vs. II (B)— .0000 III (A) vs. Ill (B)— .0000
IV (A) vs. IV (B)— .0000 V (A) vs. V (B) — .4954
individually at the same rate as did the normal animals, once every five minutes. Thus, it is apparent that in the absence of vision no imi- tative rise will occur; possible response to pres- sure stimuli does not obtain. The normal rate and type of surface rises in these blinded forms indicates that this pattern of behavior is not dependent on vision for its proper execution though imitative response by one fish to another is.
Locomotok and Respiratory Activity in Waters of Low Oxygen Content.
In previous experiments (Shlaifer & Breder, 1940) it was found that when the oxygen content of the water was increased from 2.50 cc. to 5.60 cc. per liter, the rate of respiratory activity (surface rises) decreased significantly though the locomotor activity remained the same. It be- comes desirable, therefore, to determine the respiratory activity and, to a minor extent, the locomotor activity at very low oxygen levels. Small tarpon, incidentally, are relatively hardy forms and are adaptable to a variety of situations. They endure handling in the laboratory remark- ably well and would be excellent laboratory material for many lines of research were they to be found more frequently and in greater abund- ance. They may be found both in the sea and in land-locked pools which are brackish or fresh-
water. Some of these pools have relatively little dissolved oxygen but the tarpon survive.
Materials and methods. Tarpon were placed in isolation in 7 liters of standing sea water in 8-liter rectangular battery jars whose dimensions were 20.5 cm. by 18 cm. and 21 cm. deep at the 7-liter mark. The water temperature range was 19-22 degrees C. The rates of surface rises and locomotor activity were determined for 15-minute periods. The rate of locomotor activity was determined by an observational technique which is fully described elsewhere (Shlaifer, 1938). Briefly, 3-crn. squares were ruled in red India ink on all four vertical sides of the rectangular battery jar. Using the eye of the tarpon as an anatomical landmark, the number of squares, actually cubes when projected in space, traversed in a 15-minute period was multiplied by 3 to give the results in centimeters. Since this tech- nique is not as accurate as the simple observation of surface rises and since the experimental vessels, considering the size of the tarpon, were quite small and thus limited activity, the rate of surface rises in this set of experiments may be considered the more important feature. Oxygen content was determined by means of the permanganate modification of the Winkler method.
Results. Conparing the data in Table II with the results of Shlaifer & Breder (1940), it is seen that at the lower oxygen content the rate
58
[XXVI: 11
Zuologica: New York Zoological Society
of respiratory rises increases significantly and the centimeters traversed per rise decreases. The significantly lower rate of locomotor activity at the lower oxygen level may be due primarily to the distinctly smaller vessel in which the tarpon were kept in these experiments rather than to the low oxygen content. As previously mentioned, Shlaifer & Breder (1940) found that while raising the oxygen content from 2.50 to 5.60 cc. per liter in the same aquarium reduced the rate of respiratory rises it did not affect activity. At any rate, the number of surface rises increases at the lower oxygen content de- spite the decreased activity.
ously listed. In the first four experiments standing sea water was used; in the fifth, sixth, and seventh, running sea water. In all cases the battery jars were filled to capacity. In the standing water series, a fine wire screen cut so as to insure a tight fit was placed inside the battery jar at the 7-liter mark and in Expts. 5-7 a similarly tight-fitting wooden screen was placed at the same level. In each test the experimental tarpon was allowed a 48-hour period of acclima- tization in the battery jar with access to the surface. At the end of that time the screen was put in place and the time and oxygen content noted. Each battery jar contained only one
Table II.
The Locomotor Activity and Respiratory Rises of Small Tarpon in Waters of Low Oxygen Content.
A. This set of Experiments
B. Shlaifer & Breder (1940)3
Mean Oxygen Mean Locomotor Content cc. /liter Activity1
Mean Respira- tory Rises2
Mean cm. per Rise
1.02 304.0 3.6 84.4
2.40 480.0 2.9 165.5
1 Expressed in centimeters traversed per fish per 15-minute period of observation. Figure given is the mean of 80 such periods.
2 Expressed in surface rises per fish per 15-minute period of observation. Figure given is the mean of 80 such periods.
3 Based on Table I (AI), Shlaifer & Breder (1940). Figures given are for an isolated tarpon in 48 liters of sea water in a 50-liter aquarium. Figures for locomotor activity and respiratory rises represent the mean of 48 15-minute observation periods,
Statistical Significances (A vs. B) Locomotor Activity: .0003 Respiratery Rises: .007
Finally, it may be noted that if access to the surface is provided, tarpon will survive well in waters of low oxygen content and will utilize relatively more atmospheric oxygen.
Survival with No Access to the Surface.
The air-breathing habit in tarpon is peculiar in view of the fact that they normally inhabit fairly highly oxygenated sea water and have rather extensive gill surfaces. The value of the air-breathing habit in land-locked pools of low- oxygen content in which tarpon may be found is obvious. However, its persistence in the w-aters of the open sea may possibly be an indication of imperfectly functioning gills, despite their size. It becomes of interest, therefore, to determine the survival time of tarpon when cut off from access to the surface and thus forced to rely on dissolved oxygen. Hora (1933) states that various air-breathing swamp fishes can be “drowned” if prevented from reaching the water surface. Das (1935) states that the air-breathing loach, Lepidocephalus guntea, if prevented from reaching the surface, will be asphyxiated in a little more than an hour. These fishes, however, inhabit waters in which the oxygen content is habitually low in contrast to the tarpon of the open sea.
Materials and Methods. In Expts. 1-7 of Table III, the experimental vessels were 8-liter battery jars whose dimensions have been previ-
individual at a time. A record was kept of the number of hours between the start of the experi- mental period and the end, which in every case was at the death of the tarpon. Oxygen de- terminations were made each day and at the conclusion of the experiment. The locomotor activity and surface rising of the fish were also noted but only in a general way. As controls, individual tarpon were kept in battery jars in running and standing sea water without being screened from the surface.
In Expts. 8-13, the experimental vessel was a 56-liter rectangular assembled aquarium with transparent glass sides whose dimensions w-ere 60 cm. by 35 cm. and 27 cm. deep. This was kept constantly filled to capacity with running sea water. The bottom of the aquarium was covered with sand. Into this aquarium was placed a tight-fitting wire mesh screen containing three squares to the inch, at a level of 6 cm. above the bottom sand. The general procedure followed was the same as that described for the battery jar tests except that no observations were made for activity or surface rises.
Results. The data in Table III demonstrate that compelling a tarpon to rely on dissolved oxygen by screening it from the surface will re- sult in asphyxiation in from 7 to 128 hours. Death may occur in a relatively short time even in running sea water (Expt. 5). In the standing water tests the oxygen content at the death of
1941]
59
Shlaifer: Respiratory Behavior in Small Tarpon
the animal is high enough to maintain a tarpon indefinitely if it is permitted to respire atmos- pheric oxygen. There seems to be considerable individual variation in survival time. This may be a reflection of individual variations in meta- bolic rate. In the battery jar tests the tarpon would often make desperate and repeated futile attempts to reach the surface and, failing, would sink exhausted to the bottom, there to remain quiescent for long periods of time. In the aquari- um tests, much more area was allowed for normal swimming by the fishes; also, the position of the screen, 6 cm. above the bottom, prevented exhausting and futile attempts to reach the sur- face. Tarpon in this aquarium, even when not screened from the surface, normally swim near the bottom so that the experimental situation in this case is, except for the screen, quite normal.
In the control tests, tarpon in battery jars with access to the surface survived indefinitely even when the standing water oxygen content was quite low.
Discussion.
It is interesting to note in the model experi- ments that imitative rises may be induced by very crude objects differing appreciably in form and color. At the same time, a more finished wooden model is more successful than are the crude ones. The results in B of Table I indicate that movement rather form or color is the im- portant factor for, if the model is so manipulated that the normal rise of a tarpon is not simulated, there is no significant induced imitation, even with the wooden model. Nevertheless, a properly ma- nipulated silver wooden model is more successful than are properly manipulated objects that are distinctly cruder models. Apparently, then, form and/or color may also be involved but only in a minor supplementary way. Possibly at a distance of several inches or more from the re- acting tarpon the type of wooden model used was more visible than were the other objects. Using this imitative rising reaction, it may be
Table III.
Effect of Prevention of Surface Rises on the Survival of Small Tarpon.
Remarks
Periods of great activity and attempts to reach surface followed by periods of quiescence.
U
Tarpon very active — many attempts to reach surface.
Tarpon very active.
Activity and rises of fish increase markedly one day before death.
|
Experi- ment No. |
Water |
Oxygen Content* |
Survival in Hours |
|
I1 |
Standing |
3.39-2.20-1.60 |
53 |
|
21 |
Standing |
3.47-2.98-2.70-2.52 |
71 |
|
31 |
Standing |
4.15-3.20-1.68 |
51 |
|
41 |
Standing |
4.07-1.92 |
11 |
|
5l |
Running |
4.86 |
7 |
|
61 |
Running |
5.58 |
72 |
|
71 |
Running |
5.58 |
128 |
|
8= |
Running |
5.58 |
32 |
|
92 |
Running |
5.58 |
115 |
|
102 |
Running |
5.58 |
125 |
|
ll2 |
Running |
5.58 |
24 |
|
122 |
Running |
5.58 |
34 |
|
132 |
Running |
5.58 |
46 |
|
* In the standing water experiments, the oxygen content |
represents the oxygen content of the medium at the death of the experimental animal. In the running water series, the figures given represent the average oxygen content in cc. per liter day by day.
1 Experimental vessel is an 8-liter battery jar.
2 Experimental vessel is a 56-liter aquarium.
In several cases attempts were made to revive tarpon which, after a long period of time, were near asphyxiation and lay on their sides. They were permitted to come in contact with the surface but evidently were too far gone, for they soon died. In one case, however, three blinded tarpon, which when screened from the surface in standing water in a battery jar soon approached exhaustion and asphyxiation, did recover when the screen was removed after one hour. In that time, unlike normal tarpon, they kept rising al- most continually in attempts to penetrate a screen which they could feel but could not see and within 40 minutes lay on their sides. Das (1935) reports that the air-breathing loach will recover from partial asphyxiation if permitted to rise to the surface after being kept under a screen.
possible, by employing a great variety of objects differing in form and color but manipulated