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LIBRARY

OF THE AMERICAN MUSEUM

OF NATURAL HISTORY

PROCEEDINGS

OF THE

SOCIETY FOR

EXPERIMENTAL BIOLOGY AND MEDICINE

VOLUME X

1912-1913

EDITED BY THE SECRETARY

NEW YORK 1913

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CONTENTS:

SCIENTIFIC PROCEEDINGS (50th—54th meetings):

Communications of the fiftieth meeting, October 16, 1912. Communications of the fifty-first meeting, December 18, I912 . Communications of the fifty-second meeting, February 19, 1913 Communications of the fifty-third meeting, April 16, 1913. Communications of the fifty-fourth meeting, May 21, 1913 Recapitulation of the names of the authors and of the titles of the communications ; d é :

EXECUTIVE PROCEEDINGS (50th—54th meetings)

REGISTER OF NAMES AND ADDRESSES OF THE MEMBERS

List OF OFFICERS . , :

CLASSIFIED List OF MEMBERS. :

INDEX OF THE SCIENTIFIC PROCEEDINGS.

PEATE te

SCIENTIBIC se ROCEEDINGS:

ABSTRACTS OF THE COMMUNICATIONS. Fiftieth meeting.

Cornell University Medical College. October 16, 1912. Dr. Lee in the chair.

1 (697) A note on the mode of infection in epidemic poliomyelitis. By SIMON FLEXNER and PAUL F. CLARK.

[From the Laboratories of The Rockefeller Institute for Medical Research.|

Both in experimental and human epidemic poliomyelitis the virus has been repeatedly demonstrated in the tonsils, in the nasal mucous membrane, and in nasal washings, both from fatal and acute cases. As the experimental disease can also be produced by intranasal swabbing with the active virus it seems probable that the nasal mucosa is one at least of the sources of the virus in the outside world and also the means of its entrance to the body. The marked viability of the virus under adverse conditions such as drying, low temperature, etc., must also be considered as making for a fairly well founded theory of the nasal route as one path of the virus to and from the body.

The precise manner in which microédrganisms enter the body through mucous membranes is difficult to establish. Because we can produce experimental poliomyelitis by the application of the active virus to the nasal mucous membrane, we have in this disease a means of determining whether the virus so applied first enters the blood stream and through this the central nervous system or whether it ascends directly along the lymphatics that unite the nasal mucosa with the central meninges. In experimental polio- myelitis produced by any method of injection it is well known that the virus is present throughout the central nervous system. But after an intranasal injection, can the virus be demonstrated equally

early in all regions of the cord? I

2 SCIENTIFIC PROCEEDINGS (50).

In order to answer this question, the nasal mucous membrane of a Macacus rhesus monkey was swabbed lightly with a portion of ground cord from a recently paralyzed monkey. The monkey was killed at the end of 48 hours and the following portions of the central nervous system were removed separately and aseptically: (1) the olfactory lobes with small portions of the adjacent brain substance, (2) the medulla, and (3) pieces of the cord at different levels including the cervical and lumbar enlargements. These different portions were injected separately as suspensions into the brain and peritoneal cavity of three other Macacus rhesus monkeys.

The monkey injected with the suspension of the olfactory lobes came down in a manner typical of poliomyelitis in monkeys with definite prodromal symptoms on the ninth day, paralysis on the tenth and death on the twelfth day. At autopsy, lesions char- acteristic of the disease were observed throughout the cord.

The two other monkeys remained entirely well and have never shown any symptoms of paralysis.

The result of this experiment is definite. The virus of polio- myelitis passes from the nasal mucous membrane to the olfactory lobes and adjacent parts of the brain before it reaches the medulla or cord. This distribution is what we would expect were the ascent by the direct lymphatic path and not by the blood stream. Were the dissemination by the latter route we should expect early localization in those parts of the cord and medulla that possess an especial affinity for the virus.

2 (698) Effects on meningeal tuberculosis of the local injection of foreign leucocytes. By WILFRED H. MANWARING. [From the Rockefeller Institute for Medical Research.]

In a previous report,! it was shown that the use of foreign leucocytes as a local therapeutic agent in experimental meningeal infections in dogs is limited by the toxicity of foreign leucocytes

1Vol. IX, p. 117.

Loca INJECTION OF FOREIGN LEUCOCYTES. 3

for these animals. Rabbit leucocytes injected into the meningeal cavities of dogs invariably cause death. A single injection of horse leucocytes, however, can be safely made in normal dogs, although on repeating the injection, or on injecting horse leu- cocytes for the first time into meninges already the seat of an inflammatory lesion, death results.

The injection of horse leucocytes into the cerebral meninges of dogs, simultaneously with the inoculation of the meninges with tubercle bacilli, causes a slight delay in the development of the paralytic symptoms in about half of the treated animals. This delay, however, is very slight when compared with the great prolongation of the latent period previously observed,! after treat- ment with homologous leucocytes.

In the same report, it was shown that foreign leucocytes are much less toxic for monkeys. Both rabbit leucocytes and horse leucocytes can be safely injected into the meningeal cavities of these animals.

The study of the therapeutic control of meningeal tuberculosis in monkeys is made difficult by extra-dural leakage, when the inoculations and treatments are made by the method of lumbar puncture. The inoculations and treatments, in the later experi- ments herein reported, were therefore made through a permanent wax-trephine? opening in the skull.

The injection of foreign leucocytes into the meningeal cavities of monkeys, either simultaneously with the inoculation with tubercle bacilli, or subsequent to the inoculation has thus far given no definitely positive prophylactic or curative effects. Ina small group of monkeys, however, inoculated and treated by the method of lumbar puncture, the repeated injection of rabbit leucocytes was associated with a considerable prolongation of the latent period in one of the treated monkeys, and by a complete prevention of the subsequent tuberculosis in a second monkey. The work with monkeys is being continued.

1 Jour. Exp. Med., 1912, XV, pp. I-13. 2 Jour. Exp. Med., 1912, XV, p. 3.

4 SCIENTIFIC PROCEEDINGS (50).

3 (699) The importance of calcium in relation to growth. By FRANCIS H. MCCRUDDEN. [Rockefeller Institute Hospital, New York.)

In certain cases of retarded development there is faulty skeletal development and disturbed calcium metabolism. The bones are frail and easily fractured; large quantities of calcium are lost through the feces, and the urine is almost free from calcium. It seems probable that the retarded skeletal develop- ment is due to the lack of calcium salts available for bone growth. Other cases of retarded development show no such disturbances of calcium metabolism and the bones are of normal solidity. In these cases there is a more fundamental absence of the ‘‘ tendency to grow”’ rather than any lack of material for growth.

4 (700)

The pyramid tract in the Canadian porcupine (Erethizon dorsatus Linn.).

By SUTHERLAND SIMPSON.

[From the Physiological Laboratory, Medical College, Cornell Uni- versity, Ithaca, N. Y.]

The nerve fibers of the pyramid tract pass caudalwards from their cells of origin in the motor area of the cerebral cortex and are homo-lateral until the lower part of the medulla oblongata is reached. At this level, in the majority of mammals that have been examined, most of the fibers decussate and take up a position in the lateral column of the spinal cord on the opposite side, just ventral to the posterior horn, forming the crossed lateral pyramid tract. <A few fibers remain uncrossed and are found in the lateral column on the same side, constituting the direct lateral pyramid tract.

In man and the anthropoid apes a second uncrossed tract is found in the ventral column—the direct ventral pyramid tract. In mammals lower in the scale than the anthropoids, it is generally held that this direct ventral tract is not represented at all.

THE PyrAMID TRACT IN THE CANADIAN PORCUPINE. 5

This disposition of the pyramid tract fibers is not found in all mammals however. In the guinea-pig (v. Bechterew, Reveley), mouse (v. Lenhossek), rat (Flechsig, King) and squirrel (Weigner), and in the monotremes and marsupials (K6lliker and Ziehen), the crossed fibers run in the dorsal and not in the lateral column of the cord.

In the spring of the present year, I obtained some full-grown porcupines with the object of investigating the course of the pyramid tract fibers in this animal. The left motor cortex was located by electrical stimulation and then extirpated in the usual way. At the end of about a fortnight after the operation in each case the animal was killed, the brain and cord removed, stained by the Marchi method and sectioned at all levels. A full descrip- tion of the resulting degenerations will be published later; in this preliminary communication only the most important points will be mentioned.

In the internal capsule, pes pedunculi, pontine bundles and upper levels of the medulla oblongata, the fibers occupy the usual positions and no special comment is called for, but in the lower part of the medulla oblongata the arrangement is peculiar, and nothing similar, so far as I know, has been hitherto described in any other animal.

At the decussation of the pyramids most of the degenerated fibers cross the median raphe, pass backwards through the gray matter, and take up a position in the dorsal column of the opposite side occupying the ventral portions of the fasciculi of Goll and Burdach. A few of the crossed fibers curve outwards and enter the opposite lateral column of the cord. A very considerable number of fibers, however, remain uncrossed and are continued into the cord, forming a comparatively large and compact bundle in the ventral column extending along the margin of the anterior median fissure. Some uncrossed fibers are also found in the dorsal column of the same side but these are very scanty.

In this animal, then, the fibers of the anterior pyramid on entering the spinal cord are divided into four fasciculi, two crossed and two direct, viz: the crossed dorsal pyramid tract, the crossed lateral pyramid tract, the direct ventral pyramid tract, and the direct dorsal pyramid tract. Of these the crossed dorsal and

6 SCIENTIFIC PROCEEDINGS (50).

direct ventral tracts are much larger than the other two and can be traced as far as the lower sacral segments. The crossed lateral and direct dorsal seem to disappear in the upper thoracic region. Arranged according to the number of fibers which they contain, the order is crossed dorsal, direct ventral, crossed lateral, direct dorsal.

5 (701)

Interpolated extra-systoles, of frequent occurrence, in an other- wise normal human heart.

By M. DRESBACH and S. A. MUNFORD.

[From the Physiological Laboratory, Cornell University, Ithaca, N. Y.]

In the extensive literature upon extra-systoles about twenty writers have described the type known as the interpolated beat of the ventricle. Although such beats have frequently been pro- duced experimentally, their occurrence clinically is comparatively rare.1 Almost without exception they have been observed in cases showing gross lesions of the heart. The present case is of interest because the interpolated contractions occur persistently and frequently in a heart which, aside from a slow sinus rhythm, is otherwise normal. It furnishes a striking example of an organ on the borderland between a physiological and a strictly patho- logical condition.

T., a Chinese student at Cornell University, is in good health. He is able to take vigorous exercise, such as running, tennis, etc. About two years ago a cardiac irregularity was discovered in his routine physical examination. Prior to that time he was wholly ignorant of any disturbance in his heart, and is at no time conscious of the heart’s contractions. Polygraphic records have frequently been made during the past two years and the organ has been found beating normally on two occasions only, and but for a short time.

The tracings show extra-systoles of the ventricle which occur with considerable regularity on some days, but usually they appear at varying intervals. The normal rate of the dominant rhythm

1 Mackenzie, Lewis, Wenckebach, and others.

INTERPOLATED EXTRA-SYSTOLES. 7

averages about 60. It may go as low as 50 during rest. The extra-systoles average about 35 per minute during rest and 45 after vigorous exercise. The ectopic beat follows the normal contraction by a period averaging 14second. The pause following the extra-systole is variable; occasionally it is fully compensatory. The dominant rhythm is but slightly disturbed, as a rule. Often it is strikingly constant, and it is seldom more variable than the rhythm of many normal hearts. This is remarkable in view of the fact that in the tracings there is good evidence of retrograde contractions of the auricle which beats prematurely in response to the heterogenetic stimulus. Evidence for the retrogression is found in the absence of the ‘‘a’”’ wave at certain cycles. In place of the ‘‘a’’ wave there is often seen a wave which precedes the normal auricular systole by 3/30 to 5/30 of asecond. This prema- ture wave is also preceded by a wave practically synchronous with the extra-systole of the ventricle.

The interpretation of the curves has been uncertain because of the unusual character of the phlebograms and cardiograms and because of the difficulty in establishing proper time relations, While several explanations may be offered for the type of irreg- ularity exhibited, the evidence points to the one given as plausible, but not altogether satisfactory.

Physiologically this heart is interesting because of the following characters:

1. It very rarely has periods in which its action is absolutely normal. These periods are of short duration.

2. The normal sinus rate is slow.

3. Functionally the heart meets all ordinary demands made upon it.

4. There is a bathmotropic disturbance which causes persistent interpolated extra-systoles.

5. The number of extra-systoles is not decreased, except slightly in a few tracings, by an increase in the heart rate due to exercise. The tendency is for the number to rise with acceleration of the normal beat.

6. The pause following the extra-systole is variable. Occa- sionally it is compensatory.

7. There is strong evidence that the extra-systole of the

8 SCIENTIFIC PROCEEDINGS (50).

ventricle is often followed by a premature beat of the auricle. When the evidence of such retrograde contractions is best, the indicated time of backward conduction is 7/30 to 8/30 of a second.

8. There is no evidence of lengthened As—Vs intervals except at the extra-systoles.

9. There is a fairly fixed time relation between the normal and abnormal ventricular systoles.

10. There is often a considerable delay in the appearance of the carotid pulse resulting from the extra-systole.

11. There is a marked lack of synchronism between the carotid pulse and the “‘c’’ wave. The latter may precede the former by 1/20 of a second.

12. The site of the abnormal stimulus is either in the ventricle or some part of the conduction system, e. g., the node, or some lower point.

6 (702)

On the differences in the effects of stimulation of the two vagus nerves on rate and conduction of the dog’s heart.

By ALFRED E. COHN.

[From the Hospital of the Rockefeller Institute for Medical Research, New York.|

The effects obtained in the action of dogs’ hearts on stimulating the peripheral stumps of both vagus nerves were studied in fifty- four experiments. The dogs were anesthetized with ether without adjuvant, artificial respiration was maintained by the Meltzer- Auer method, and registration was accomplished by the galvano- metric method. When the chest was opened, curves of auricular and ventricular contractions were also inscribed. Faradic stimula- tion was employed. The secondary coil of an inductorium, fed by a 2-volt dry cell, placed arbitrarily at 50 mm., was the source of the current.

On stimulating the right vagus nerve, the usual effect was obtained; both auricles and ventricles ceased to beat, generally throughout the period of stimulation. Occasionally the ventricles escaped from inhibition, but then the impulse to contraction arose

EFFECTS OF STIMULATION OF Doc’s HEarrT. 9

and spread in an abnormal manner; the structures normally con- cerned with these functions remained inhibited.

When the left vagus nerve was stimulated in the same dog, with a current of the same strength, a difference from the effect of stimulating the right nerve was observed in 88 per cent. of the fifty-four experiments. The auricles did not cease to beat, they were merely slowed,—sometimes 100 or more beats. In one group, normal ventricular contractions ceased entirely in twenty-four cases. In a second of twenty-four other cases, a ventricular contraction followed every second, occasionally every third, fourth or more auricular beats, the mechanism being one of incomplete dissociation. Ina third group, the only effect of stimulation was an increase in the time occupied in conduction from auricles to ventricles.

In the first group when the left vagus was stimulated, as has been stated, normal ventricular activity ceased, but abnormal activity occasionally continued. The rate of the abnormal ven- tricular contractions differed from that of the slowed auricles and complete As—Vs dissociation resulted. Similar ventricular activity occurred also when the right vagus was stimulated, but the auricles, as is usual, ceased to contract.

The explanation offered for the phenomena occurring on left vagus stimulation is that the main effect consists in depressing the conduction system. In the first group, the ventricles cease to beat, because, on account of the great depression of conduction, they receive no impulses from the auricles. If the ventricular muscle is irritable, abnormal stimuli may be formed and an idioventricular rhythm result. When a slighter degree of depres- sion of conduction has taken place, every second or third beat passes along the A—V bundle and initiates a ventricular contrac- tion. A still slighter degree of depression results in a mere lengthening of the time of conduction.

The mechanism which results from stimulating the right vagus nerve and the negative chronotropic effect of the left nerve are not discussed at present.

10 SCIENTIFIC PROCEEDINGS (50).

7 (703)

The creatine content of muscle under normal conditions. Its relation to the urinary creatinine.

By VICTOR C. MYERS and Morris §S. FINE.

[From the Laboratory of Pathological Chemistry, New York Post- Graduate Medical School and Hospital.|

Though an unusual amount of attention has been devoted to urinary creatinine since the introduction of Folin’s simple colori- metric method for its estimation in 1904, relatively little considera- tion has been given to the supposedly related muscle creatine. The few figures which have been published giving the content of muscle creatine have simply served to indicate that the creatine content of vertebrate muscle is in round numbers .4 per cent., though figures for different animals have shown individual results varying from .3~-.5 per cent. We have estimated the creatine concentration of muscle in a number of the common laboratory animals, rabbit, dog, cat, guinea pig, monkey, and likewise in man, in a few instances, where we have been able to obtain good samples at autopsy. Our muscle analyses on 20 normal rabbits and 5 dogs have yielded very uniform figures and indicate that the creatine concentration of rabbit muscle is .52 per cent. and of the dog muscle, .37 per cent. Our data on the muscle of the other species are as yet insufficient to warrant special comment. This uniformity recalls the constancy of the daily creatinine elimination first noted by Folin.

It is a curious fact that the creatinine coefficient of the rabbit is fully a third higher than that generally found in man and various experimental animals, dog, pig, and guinea pig. In forty rabbits, the average coefficient has been found to be 14.3 while for a healthy man, the normal coefficient is about 9, and for the dog, the average is probably a little lower (for 3 animals it was found to average 8.4). Comparing these values with those for the creatine concentration of the muscle (rabbit .52, man .39 and dog .37 per cent.), an interesting, and, as we believe, more than an accidental relation- ship is revealed.

CREATINE OF MuscLE UNDER NorMAL CONDITIONS. Tor

In view of the lack of proof of the connection of creatine and creatinine in metabolism, our original experiments were planned in an endeavor to ascertain whether in a given animal, in this case the rabbit, there was a constant relationship between the total creatine of the body and the daily creatinine. This ratio was ascertained in a series of one growing and ten adult rabbits. It was not absolutely constant, and appeared to vary with the weight of the animal, being 53.3 : 1, in an animal of 1.39 kilos and 44.7 : 1 where the weight was 2.13 kilos. For five animals of nearly the same weight, 1.9-2.1 kilos, comparatively constant ratios, 44.7, 45.0, 44.4, 44.4, and 44.9 : I were obtained.

In a further attempt to ascertain any relationship between body creatine and urinary creatinine, the figures for the creatine concentration of the body were arranged in order of the creatinine coefficients. The first five adult animals with an average coeffi- cient of 13.6 had an average body creatine concentration of .170 per cent., while the second five animals with an average coefficient of 15.0 had a creatine concentration of .193 per cent.

Our fasting experiments below indicate that the amount of creatine remaining in the body after starvation bears a relation- ship, not only to the amount of creatine lost in the urine during this period, but also to the amount of the creatinine elimination.

An interesting observation with regard to the creatinine, in the series of eleven normal animals, is that the amount of its average daily elimination followed that of the body weight in every case. This is in accord with Folin’s original statement that body weight appears to be the most important factor in determining the amount of its elimination.

It is not supposed that these experiments offer any definite proof of the origin of the urinary creatinine from muscle creatine or some common precursor substance, but in view of the fact that no data have been adduced to show such a relationship, these experiments may be of value as advancing this hypothesis.

12 SCIENTIFIC PROCEEDINGS (50).

8 (704)

The creatine content of muscle during starvation and its relation to urinary creatine.

By VICTOR C. MYERS and Morris S. FINE.

[From the Laboratory of Pathological Chemistry, New York Post- Graduate Medical School and Hospital.|

There has recently arisen some little discussion with regard to the creatine concentration of muscle during starvation. Data have been submitted to show that inanition in the rabbit results in an increase in the content of muscle creatine, and it has further been argued that there is an actual increase in creatine formation. In other quarters, it has been claimed that starvation (experiments with the dog) produces a marked decrease in the percentage con- tent of muscle creatine.

From nine experiments which we have already completed on starving rabbits, we can agree with both of these observations as regards an increase or a decrease in the content of the muscle creatine. In three experiments, a decided increase in the content of creatine in muscle has been found; in one the per cent. of creatine was normal, while in five it was even more strikingly below normal. In addition to the increased or normal creatine content of muscle, the first four animals mentioned showed an increased percentage content of creatine in the body. This we are not inclined to ascribe to an increased creatine formation.

The reason for this increased or decreased content of body and muscle creatine appears to be satisfactorily explained by our results. The animals having an increase in the content of muscle creatine eliminate a comparatively small amount of creatine in the urine, while those in which the muscle and total body creatine has been considerably depleted, eliminate an equally large amount of creatine in the urine. In other words, the content of muscle creatine during starvation is dependent upon the amount of and the rate of creatine excretion in the urine. Just why some animals eliminate creatine more rapidly than others, we are as yet unable to explain, although we assume that this is connected with the length of the fast and the state of nutrition of the animal. The

REVERSAL OF THE CARDIAC MECHANISM. 13

rate of the loss of creatine appears to closely parallel that of the total nitrogen.

Still an added factor in this loss of creatine from the body is the excretion of creatinine. In experiments where the creatine of the urine plus that of the tissue does not entirely account for the creatine which should normally be present in the body, it is found that a considerable amount of creatinine has been eliminated in the urine, e. g., in the case of a comparatively long fast. When this creatinine in terms of creatine is added to the creatine of the tissue and urine, this total exceeds the total normal body creatine by about 10 per cent., this excess probably representing the amount of creatine and creatinine formation. It would seem probable from these data that during starvation, the creatine storehouse was depleted not only by a loss of creatine in the urine, but also by the loss of creatinine.

It has been assumed for some time that the creatine appearing in the urine during starvation and in various pathological condi- tions was derived from the creatine of the muscle, and measured the amount of muscle disintegration, though so far as the authors are aware this point has never been conclusively demonstrated. In our experiments, we have found that when the weight of the creatine excreted in the urine was added to the weight of creatine still remaining in the body after the period of starvation, the amount of creatine was only slightly below that which would have been found in the body had the animal been killed prior to starvation. This would seem to demonstrate that the creatine appearing in the urine in starvation was derived from the creatine of the muscle.

9 (705)

Reversal of the cardiac mechanism. By HORATIO B. WILLIAMS and HENRY JAMES.

[From the Physiological Laboratory of Columbia University, New York.|

The subject of investigation, H. M., came under observation at the Vanderbilt Clinic July 15, 1912. He has had a persistent

14 SCIENTIFIC PROCEEDINGS (50).

diarrhea for a year with several watery stools a day. Otherwise he has been well until three months before admission to the clinic.

During these three months and subsequently, he has suffered from attacks of dizziness of increasing severity. In one of these attacks he fainted and fell in the street. Muscular effort increases the giddiness. He has had a good deal of headache. He is very drowsy and is annoyed by numbness and tingling of the hands and feet.

Until the onset of symptoms he had been a heavy drinker. He denies lues and gonnorrhea. The Wassermann test was negative. The blood and urine are normal. The heart is not enlarged. The sounds are faint but clear, and there are no murmurs. The third sound has been distinctly audible at most examinations and has been recorded graphically. The pulse is regular, 40 per minute. Systolic bloodpressure varies between 95 mm. and 110 mm. and diastolic pressure is usually about 65 mm. The electro- cardiograms show that the heart beat is initiated by the ventricles, the auricular beat succeeding the ventricular after the usual con- duction interval. This is evidenced by the presence of an inverted P between R and T in leads IJ and III. In lead I, P is of very small amplitude, but can be clearly distinguished on close inspec- tion and stands in the same relation to R and T as in the other leads.

This interpretation of the electrocardiograms has been con- firmed beyond reasonable doubt by examination with Roentgen rays and fluoroscope. The contractions of the auricle can be distinctly seen.

We are not yet ready to offer an explanation for the peculiarly slow intrinsic rhythm of the auricles which permits the ventricle to initiate the beat. Neither atropin nor digitalis has any measur- able effect on the condition. The subject is still under observation.

Rote oF Lrporps IN NARCOSIS. 15

10 (706)

The réle of lipoids and particularly lecithin in narcosis. By B. KRAMER.

[From the Physiological Laboratory of Cornell University Medical College, New York City.]

Following the discovery of anesthetic properties of ether by Jackson and Morton in 1846, numerous theories appeared in the literature which aimed to explain this important phenomenon. Of these the well-known Meyer-Overton theory is the only one that has survived the test of time. It reads as follows: ‘‘The narcotiz- ing substance enters into a loose physio-chemical combination with the lipoids of the cells, perhaps with the lecithin, and in doing so changes their normal relationship to other cell constituents through which an inhibition of the entire cell chemism results.” Evidently this theory casts no light upon the nature of the altera- tions in cell chemism that follow. It remained for Verworn, Mansfeld, Biicher and Heaton not only to demonstrate the nature of these changes in cell chemism but also to show that the anes- thetic state itself is in all probability dependent upon these alterations.

Reicher, who demonstrated the constant presence of lipoidemia after narcosis, explained this as being a protective mechanism; the lipoid molecules acting as amboceptors uniting with anesthetic and thus protecting the more vitally important brain lipoids. Nerking attempted to prove this experimentally by injecting various quantities of a I to 20 per cent. lecithin emulsion in normal salt solution intravenously, intraperitoneally, intraspinally or sub- cutaneously in animals which had been narcotized or were about to be anesthetized and claimed to have shown that ‘‘ The injection of lecithin has an undoubted influence upon the duration and after effects of anesthesia in that it shortens its duration, brings about a more rapid return to consciousness and eliminates unpleasant after effects.”

A careful analysis of Nerking’s work shows it to be scarcely worthy of serious consideration, owing to its lack of exactness in the dosage of the narcotic and the indefiniteness of the criteria used.

16 SCIENTIFIC PROCEEDINGS (50).

Nevertheless, the importance of his conclusions, if confirmed, is quite evident if this could be done with the above mentioned experimental defects eliminated.

In order to accomplish this all anesthetics were given intra- venously, a 5 or Io per cent. ether solution in normal salt solution being used, and this was injected at definite rates; the lecithin emulsion was also injected directly into the vein. The criteria used were the appearance and disappearance of the corneal reflex, or, when this did not occur, the loss of cutaneous pain sensation was used. Other criteria were the time when the animal first raised its head, when it first assumed the erect posture, and when all ataxia disappeared. The results obtained seem to point over- whelmingly to the following conclusions:

1. That the intravenous injection of 5 to 30 c.c. of a 5 or 10 per cent. emulsion of lecithin, depending upon the size of the animal used, does not interfere with the induction of anesthesia and that this can be accomplished as readily in animals thus injected as in controls.

2. That in the majority of experiments, lecithin has no effect upon the rapidity with which the various phenomena which indicate the animal’s recovery from the effects of anesthetic appear, in fact, in most cases, it retards their appearance.

The above experiments do not seem to bear out Reicher’s assumption as to the cause of the lipoidemia and the explanation of this phenomenon still remains an open question.!

II (707)

Habit and its relations to the nervous system in the earthworm. By ROBERT M. YERKES.

[From the Psychological Laboratories, Harvard University.]

This is a preliminary report of an investigation now in progress, the purpose of which is (a) to demonstrate whatever ability the earthworm may have to acquire habits of a certain order; (0) to discover the characteristics of any habits which appear; (c) to

1 The complete report of this work will appear in the Journ. of Exp. Med. for February, 1913.

HaBiIT IN THE EARTHWORM. 17

enumerate and evaluate the various external and internal influences on habit-formation; (d) to ascertain the degree of permanency of the habits and (e) to discover their relations to the anterior ganglia (brain).

By means of a T-shaped maze constructed from plate glass, specimens of the manure worm, Allolobophora fetida, were tested. The maze was placed with the stem directed toward the light. Across one of the arms a piece of sandpaper was placed and, just beyond it, a pair of electrodes. The other arm was left open so that the worm might escape to an artificial burrow. The worms were driven into the T by light and the chief motive for escape therefrom was the tendency to avoid light. It was the purpose of the test to demonstrate (a) any ability which the manure worm may possess to acquire a direction habit and (0) to associate the tactual experience of contact with sandpaper with the electrical shock which regularly followed the tactual stimulus in case the worm continued to move forward after reaching the sandpaper.

Trials were made in daily series varying in number from five to twenty. The five-trial series were found, on the whole, most satisfactory.

Referring now exclusively to the results obtained for a single worm which has been under observation since October, 1911, the following data may be presented. (1) Allolobophora is capable of acquiring certain definite modes of reaction. (2) Modifications appear as the result of from twenty to one hundred experiences. (3) The behavior is extremely variable because of variations in external conditions and in the condition of the worm itself. (4) There is a tendency to follow the mucous path through the appa- ratus but this is not sufficiently strong or constant to yield perfect results. (5) The following are the chief modifications which have been noted: (a) Increased readiness to enter the apparatus and to desert it for the artificial burrow; (b) apparent ‘‘recognition”’ of the artificial burrow which is used as ‘‘exit tube”’; (c) a gradual increase in the number of avoidances of the sandpaper and of contact with the electrodes as a result of the ‘‘warning’’ influence of the sandpaper; (d) the disappearance of the early tendency to re- trace the path through the stem of the T; (e) the similar disap- pearance of the tendency to turn back after progressing well

18 SCIENTIFIC PROCEEDINGS (50).

toward the exit tube. (6) The correct performance of a thoroughly ingrained habitual act, of the kind studied in this investigation is not dependent upon the “‘brain”’ (portions of the nervous system carried by the five anterior segments), since the worm reacts appro- priately within a few hours after its removal. (7) As the “‘brain’”’ regenerates, the worm exhibits increased initiative, its behavior becomes less automatic, more variable. (8) Within four weeks after the operation the regenerated segments appear superficially complete and the worm naturally burrows in a mixture of earth and manure. (9) Two months after the removal of the “brain,” during the last four weeks of which period no training was given, the habit had completely disappeared from worm No. 2, the subject to whose responses this paper is devoted, and in its place there appeared a tendency to turn in the opposite direction to that demanded in the training. (10) Systematic training for two weeks resulted in the partial re-acquisition of the original direc- tion-habit.

The general results which have just been stated are subject to modification in the light of additional data. To the experimenter, it seems that the particular individual which has been longest under observation is in many respects exceptional. It is perfectly clear, however, from results obtained with six individuals that important modifications in behavior appear as the result of train- ing. It is equally certain that direction-habits are not readily acquired.

It is the purpose of the experimenter in the continuation of the investigation to pay especial attention to the relation of the nervous system to modifications of behavior.

12 (708)

Preliminary note on the action of glucose upon the amount of epinephrin in the blood. By ISAAC OTT and JOHN C. SCOTT. [From the Laboratory of Physiology, Medico Chirurgical College, Philadelphia.]} The modern theory of experimental diabetes is that a glyco- secretory center is located in the medulla, from which impulses

HORMONES OF THE SECRETION OF MILK. 19

pass down the cord, emerge in the splanchnics, and go to the liver to increase the transformation of glycogen into glucose. It is held by some that as the splanchnics contain the secretory fibers of the adrenals, that these impulses from the glyco-secretory center increase the amount of epinephrin, which mobilizes the glycogen of the liver and thus produces a diabetes. It is well known that epinephrin is a stimulant of the sympathetic nerves, hence it is a stimulant of the splanchnics. We have found the injection of glucose per jugular in the cat increases the amount of epinephrin in the blood, as shown by the intestinal strip of the rabbit. Hence we have here a circle: epinephrin stimulates the secretory nerves of the adrenals to produce epinephrin, which via the glycogen of the liver produces more glucose, which in its turn generates more epinephrin. We have also found the other sugars to increase the amount of epinephrin in the blood. Pilocarpin, skatol and indol also augment the amount of epinephrin in the blood.

13 (709)

Preliminary note on the inhibitory and synergistic hormones of the secretion of milk.

By ISAAC OTT and JOHN C. SCOTT.

[From the Laboratory of Physiology, Medico Chirurgical College, Philadelphia.|

We have studied on the goat the hormones which inhibit the milk secretion. We have found that the ovary inhibits the action of infundibulin, pineal gland, corpus luteum and thymus upon the secretion of the mammary gland. Pancreas, spleen, iodothyrin- parathyroid and adrenalin also inhibit the action of indundibulin. Orchitic extract increases the activity of infundibulin, thus being a synergistic agent. Egg albumen does not inhibit the action of infundibulin.

20 SCIENTIFIC PROCEEDINGS (50).

14 (710) Heterochromosomes in mammals. By 'H. E. JORDAN. [From the Department of Anatomy, University of Virginia.]

Heterochromosomes have now been reported for the male germ cells of the following mammals: man and rat (Guyer, ’10); armadillo (Newman and Patterson, ’10); opossum (Jordan, ’11); guinea-pig (Stevens, ’11); and bat (Jordan, ’12). Winiwarter and Sainmont, ’09, report a longitudinally split ‘‘monosome”’ in the oécyte of the cat.

A comparative study of mammalian spermatogenesis reveals the absence of typical heterochromosomes in mongoose,* cat, squirrel, rabbit and pig. Heterochromosomes are clearly present at synapsis and prophase in the primary spermatocytes of the following forms: white mouse, sheep, horse, mule, dog and bull. Regarding dog, rabbit, and the monkey, the evidence is not yet decisive.

At certain stages the heterochromosomes (chromosome-nu- cleoli) appear single (accessory; monosome), at others double or bipartite. The latter appearance suggests a pair of idiochromo- somes; but the body is more probably a split accessory.

The absence of discernible heterochromosomes in the male, and their conspicuous presence in the female, of the cat indicates their presence in one or the opposite sex in all forms. If this hypothesis can be supported by evidence from the odcytes of mongoose, squirrel, pig, rabbit and similar forms, cogent additional confirmation is given to the idea of a special significance of het- erochromosomes, probably in connection with the determination of sex.

A simple explanation of sex-determination suggested by these and other facts — and one in apparent accord with a large body of experimental and cytological data— would seem to be to regard

* This material was collected at the temporary Marine Biological Station of the Carnegie Institution of Washington at Montego Bay on the expedition to Jamaica,

B. W. I., in February and March, 1912, under the directorship of Dr. Alfred G. Mayer.

DETERMINATION OF GLYCOGEN IN THE LIVER. 21

the heterochromosome-complex or ‘‘ X-element’”’ (Wilson), con- tributed by the spermatozo6én, as an inhibitor to male sex. Regarded in terms of Mendelian concepts, however, an apparent contradiction results in that the presence of a determiner (inhibitor to maleness) would here have to be recessive to its absence. But in terms of a quantitative interpretation two X-elements in the zygote would prevent, one X-element permit, the development of male sex. Similarly with respect to the phenomenon of sex- limited heredity: the X-element may act as the inhibitor in the female to the male-limited character.

15 (711)

A comparison of chemical with microchemical methods for the determination of varying amounts of glycogen in the liver.

By G. Y. RUSK.

[From the Hearst Laboratory of Pathology and Bacteriology, Uni- versity of California.]

In collaboration with Dr. F. P. Gay, a study has been made of the glycogen in the livers of 22 rabbits, comparing the chemically determined amount with the histological appearance with a view to finding the value of the latter for comparing small differences in glycogen content. Pfliiger’s method was employed as far as the conversion of glycogen to glucose and for the quantitative estima- tion of the latter Bertrand’s method was used. For the histological picture, Best’s carmine method and Langerhans’ modification of Ehrlich’s iodine method were employed.

The