Samples 14 to 25.-Drawn off at, as nearly as possible, halfminute intervals, between 4.50 and 5 p.m. Death.

At 5 p.m.-Specimens 2 and 3 are firmly clotted; the tubes can be inverted. Specimen 4 is liquid. Specimen 5 is partly liquid. Specimens 6, 7, 8, 9 are entirely liquid. Specimens 10, 11, 12 are distinctly clotting. Specimens 13 to 25 are perfectly liquid.

At 5.15 p.m.-Specimens 1 to 9 as before. Specimens 10 and 13 are half-solid. Specimens 11 and 12 are firmly clotted; can invert the test-tubes. Specimens 14 to 25 still perfectly liquid. Observations discontinued for the day.

Next morning.-Distinct cylinders of clot are shaken out of the tubes containing specimens 2, 3, 10, 11, 12, 13, the other specimens being still perfectly liquid.

This, as has been said, is only one of five experiments in which the clamping of the trachea was found to restore the coagulability to peptone blood.

I was now anxious to determine further whether an increased coagulability could be determined to exist in peptone blood returning from tetanized muscles. I was not able to satisfy myself that this was actually the case, but in the course of the experiment I came across the fact, which, indeed, might have been inferred from the facts about peptone blood which had been already determined. This was the fact that the venous blood still preserves its coagulability when the arterial blood has become uncoagulable by a peptone injection. This holds, I think, universally of peptone blood. With regard to the question of the relative coagulability of portal as compared with systemic venous blood, I have observed, in two experiments, a superior coagulability of the portal blood, but I do not, in the absence of further experiment, desire to lay any stress upon the observation.

Enough has, however, been elicited,' with regard to the conditions of coagulability in peptone blood, to justify the statement that the

1 The facts which have been established above-viz. the retention of normal coagulability in peptone venous blood and the restoration of coagulability to peptone arterial blood by clamping the trachea-seem, when taken in connexion with Lahousse's observations (Du Bois' Archiv., 1889) on the great diminution of CO, in peptone blood, and Bohr's observations (Centralblatt f. Phys., Sept., 1888) upon the greatly reduced excretion of CO2 after peptone injections, to point strongly to the conclusion that the modification introduced by peptone in the coagulability of the blood is, in great part at least, attributable to a disturbance of its normal gaseous composition. Such an hypothesis would explain the restoration of coagulability to peptone blood on passing a stream of CO2 gas through it; and it would further

distribution of the areas of the negative phase of coagulation after an injection of tissue-fibrinogen would be explicable upon the assumption that it was conditioned by the presence of albumose, and that it was only where this influence was in abeyance, owing to an excess of CO2, that the coagulating influence of the unaltered tissue-fibrinogen was free to exert its full effect.

Lastly, we have to examine whether it is true that—

(7). A negative phase makes itself felt in full force only in the case of such animals as are markedly susceptible to the anti-coagulative effect of albumose injections.

With respect to this question it may, I think, be asserted with confidence that the dog, which is, as far as is known, the only animal in which albumoses can be relied upon to keep the blood permanently liquid, is also the only animal in which the negative-phase, after tissuefibrinogen injections, can become absolute, i. e. can lead to an entire loss of spontaneous coagulability.

With regard to the occurrence of a negative phase in the rabbit after tissue-fibrinogen solutions which are free from albumose, I will quote the following protocols, rabbit 100.

Rabbit 100, June 26th, 1891.-Injected 20 to 25 cc. of a filtered 1 per cent. Na2CO3, solution of the washed acetic acid precipitate into the jugular vein. No apparent result, and no intravascular coagulation detected upon post-mortem examination, when the animal was killed a few minutes after by drawing off the blood from the carotid. The blood clots in 2 minutes when a stream of CO2 is passed through it; it also clots rapidly on dilution with water. Spontaneous clotting

explain the fact that the addition of peptone to blood is comparatively ineffectual in vitro.

Similarly it would explain the fact, put on record by Fano, that an injection of peptone to be effectual must be made very rapidly. This observation of Fano's, I may observe, is perfectly correct. I have repeatedly run in as much as 4 to 5 grs. of peptone per kilogramme in a dog in the form of a very concentrated solution without producing the characteristic convulsive dyspnoea obtained upon rapid injection of 0.3 to 0.5 grs. per kilogramme in the form of a 10 per cent. solution. The difficulty in rendering the blood liquid by a peptone injection after the administration of morphia is also, I believe, connected with the difficulty of obtaining the customary dyspnoeic reaction under such circumstances. In a word, the phenomena in the case of albumose injections may be summed up in the proposition-no dyspnoeic reaction, no loss of coagulability.

begins in 30 minutes, and the blood becomes firm at the end of 45 minutes.

Rabbit 101.-Injected 20 to 22 cc. of the 1 per cent. Na,CO, solution into the marginal vein of the ear through an hypodermic needle. No result apparent from this injection. Bled to death by opening the carotid. No intravascular coagulation to be detected by post-mortem examination. The collected blood at first shows no sign of spontaneous coagulability, but an immediate coagulation is obtained by passing a stream of CO, gas through it. Similarly, dilution with water or addition of some of the acetic acid precipitate produces immediate coagulation. Blood begins to clot spontaneously in 25 minutes.

It is thus seen that a negative phase of coagulation, though not by any means a pronounced one, can be obtained with tissue-fibrinogen in the rabbit. I however have succeeded in obtaining quite as marked a retardation of coagulability in the rabbit by the injection of ordinary albumoses.

With regard, again, to the negative phase in the cat, I have not in my experiments succeeded in obtaining any such marked negative variation.

With this I have completed such evidence as I am able to offer in support of the hypothesis I have advanced to explain the interconnexion of the positive and negative phases observed after tissuefibrinogen injections.

NOTES ADDED IN PRESS.

A.-Hoffmeister (Ztschft. f. Phys. Chem., 1880), has shown, in connexion with pus, that the mere addition of an alkali in the cold, splits off a large quantity of "peptone" from the leucocytes. These leucocytes of course constitute one of the mother-substances of tissue-fibrinogen.

B.-A copious excretion of albumoses or peptone also takes place in the urine of rabbits after hypodermic injections of sterile-fibrinogen solutions. The urine of such rabbits is acid on reaction. It gives no coagulum on boiling, but gives a biuret reaction. It gives a heavy flocculent precipitate on addition of alcohol. This precipitate when collected will dissolve readily in either cold or boiling water (even after it has been standing for three or four days under absolute alcohol), and will then give very distinct xantho-proteic and biuret reactions.

P.S.-The tissue-fibrinogen employed in the experiments reported above was in all cases prepared from bulls' testicles.

X.

CROP AND STERNUM OF OPISTHO COMUS CRISTATUS: A CONTRIBUTION TO THE QUESTION OF THE CORRELATION OF ORGANS AND THE INHERITANCE OF ACQUIRED CHARACTERS. BY HANS GADOW, PH. D., M.A., Strickland Curator and Lecturer on the Advanced Morphology of Vertebrata in the University of Cambridge. (Plates VII. and VIII.)

[COMMUNICATED BY D. J. CUNNINGHAM, M.D., f.r.s.]

[Read JUNE 22, 1891.]

SEVERAL adult specimens of Opisthocomus in the Cambridge Museum, and a series of well-preserved nestlings and embryos entrusted to me for examination by the Rev. Dr. Haughton, have enabled me to inquire into the peculiar structures of this neotropical bird. This inquiry revealed an instance in which an obviously primary modification, itself referable to mechanical strain during the life of the adult, seems to have caused other organic changes which are repeated in the embryo at a time before such a strain could come into play. It is easily demonstrated, by examination of the embryos, that these characters are inherited, but if, and how, they were acquired, is a question which necessitates a special investigation.

Six or seven similar cases I have recently published elsewhere.1 The alimentary canal, notably the peculiar crop of the Hoazin, has been well described in its general features by L' Herminier; but it has hitherto never been figured correctly, nor has its correlation

2

1 64 Description of the Modifications of Certain Organs which seem to be illustrations of the Inheritance of Acquired Characters in Mammals and Birds."Zoologische Jahrbücher, Abtheilung f. Systematik, Bd. v. (1890), pp. 629–646, Taf. xliii., xliv.

2 "Recherches anatomiques sur quelques genres d'oiseaux rares ou encore peu connus sous le rapport de l'organisation profonde. Par L'Herminier, médecin à la Gouadeloupe."-Annales des Sciences naturelles, 2de série, Tome 7ème. Zoologie, 1838, pp. 96-107, § 1. Sur le Sasa, Opisthocomus (Hoffmansegg).

with other organs been examined. After removal of the skin from the breast of an adult bird there appears a huge, apparently simple sac, which extends from the level of the upper ends of the coracoid bones down to within 2 cm. of the hinder margin of the sternum. The sac is formed by an enormously elongated, widened, and doubledup portion of the middle of the œsophagus, and is consequently a true crop. The originally anterior and ventral margins of this œsophageal loop are much bulged out, while the posterior and dorsal margins of the loop touch each other, and are partly connected by loose tissue. The whole loop is, moreover, turned sidewards, so that its upper or cervical half lies on the left, the lower or thoracic half on the right side of the breast. The walls of the crop are greatly thickened, partly owing to the strongly-developed outer or annular muscular coating, and partly through the presence of about twenty prominent and rough folds, which, parallel to each other, project from the ventral and lateral walls into the lumen of the organ. Each of these folds averages about 6 mm. in breadth and 3 mm. in height. Some of the folds are continued into that part of the oesophagus which connects the crop with the proventriculus. This portion is about 12 cm. long, and only 1 to 2 cm. wide, twisted and irregularly constricted. It passes, of course, into the thorax between the clavicles, but, owing to its length and bulk in general, it has shoved the stomach so far back that the gizzard, in spite of its smallness, appears partly below the left posterior margin of the sternum. The last 1.5 cm. of the œsophagus are narrow, very thin-walled, and smooth inside. The proventriculus is small, less than 2.5 cm. in length, and scarcely much wider than the duodenum; it is much constricted off from the gizzard, which latter is of the size and shape of a large olive. The walls of the gizzard are thin and weak, although they are lined with a

1 Dr. E. P. Wright has kindly drawn my attention to the following Paper which had escaped my notice :-"On the Habits and Anatomy of Opisthocomus cristatus," Illig., by Dr. C. G. Young. Notes from the Leyden Museum, vol. x., 1888, pp. 169-174, pl. VIII. Dr. Young has observed the "stinking pheasant" in its native haunts in British Guiana. The birds live together in great numbers on the low shrubs bordering the tidal portion of the Berbice river, especially on Drepanocarpus lunulatus and Caladium (Arum) arborescens, the leaves, possibly also the seeds, of which plants they eat. They are entirely arboreal, build a loosely constructed nest on the top of a low bush, and most probably feed their young from the crop. The young, when hatched, are covered with a light coat of brown down, and at once creep about with the assistance of their sharply hooked claws. Dr. Young's description and figures of the crop, stomach, and windpipe are somewhat peculiar, and justify my introductory remark.