344 MR. OWEN ON THE GENERATION OP THE MARSUPIAL ANIMALS. 



21st, 30th, and 38th days of uterine gestation : no material alteration was, however, 

 observable till after the death of the young Kangaroo of the previous year, which took 

 place on the 25th day, when the brown secretion first began to appear, and the nipple 

 that had been in use, to diminish. 



As parturition took place in the night, the mode of transmission to the pouch was 

 not observed. No blood or albuminous discharge could be detected on the litter, nor 

 any trace of it on the fur between the vagina and orifice of the pouch ; but these 

 might have been removed by the mother. The appearances presented by the little 

 one thus detected within twelve hours after being deposited in the pouch were as fol- 

 low : — It resembled an earth-worm in the colour and semitransparency of its integu- 

 ment, adhered firmly to the point of the nipple, breathed strongly but slowly, and 

 moved its fore legs when disturbed. Its body was bent upon the abdomen, its short 

 tail tucked in between the hind legs, which were one third shorter than the fore legs, 

 but with the three divisions of the toes now distinct. The whole length from the nose 

 to the end of the tail, when stretched out, did not exceed 1 inch 2 lines. 



On the 9th of October I again examined the pouch : the young one was evidently 

 grown, and respired vigorously. I determined to detach it from the nipple for the 

 following reasons : 1st, to decide the nature of the connexion between the foetus and 

 nipple ; 2ndly, to ascertain, if possible, the nature of the mammary secretion at this 

 period ; 3rdly, to try whether so small a foetus would manifest the powers of a volun- 

 tary agent in regaining the nipple ; and, lastly, to observe the actions of the mother 

 to effect the same purpose, which one might presume would be instinctively analogous 

 to those by means of which the foetus was originally applied to the nipple. 



With respect to the first point, I was aware that the Hunterian dissections as ex- 

 hibited in the preparations in the Museum of the College, and the observations of 

 Mr. Morgan * and Mr. Collie -f-, concurred in disproving the theory of a vascular 

 mode of connexion between the mammary foetus and the nipple ; nevertheless, as a 

 discharge of blood had been stated by Geoffroy St. Hilaire to accompany marsupial 

 birth, or the spontaneous detachment of the foetus from the nipple :}:, and even the 

 anastomoses and distribution of the continuous vessels in the neck of the foetus had 

 been speculated on by him §, it became desirable to have ocular demonstration of the 

 real state of the facts. The foetus retained a firm hold of the nipple : when it was 

 detached, a minute drop of whitish fluid, a serous milk, appeared on the point of the 



* Transactions of the Linnean Society, vol. xvi. p. 459. 



t Zoological Journal, No. xviii. 



X " Car le sang aper9U k la liti^re est un indice qu'a ce moment le foetus s'est detache de la tdtine, et qu'il 

 est n^ definitivement k lamanifere des marsupiaux." — Geoffroy St. Hilaire, Annales des Sciences Naturelles, 

 torn. ix. p. 342. 



§ " Des vaisseaux nourriciers se repandroient-ils des parties du pharynx le long et entre les lames de la tra- 

 ch6e artfere pour entrer dans le coeur, et (conjecture de M. Serres,) la gland thyroide seroit-elle le point de 

 leur reunion? J'ai manqu^ des sujets pour verifier ses apergus." — Geoffroy St. Hilaire, Mem. du Mu- 

 seum, torn. xix. p. 406. 



