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Dr. M. Watson. 



membrane, which was undoubtedly the chorion, agrees with that 

 described in the dog, cat, and other Carnivora, not only as regards its 

 form, bnt in the fact that a few blood-vessels were prolonged outwards 

 from its villous or placental portion to ramify in its non-placental area. 

 Judging from the extent to which the uninjured pole of the chorion, 

 which accommodated the anterior portion of the foetus, was prolong-ed 

 outwards from the placental margin, it did not appear probable that 

 any portion of what (with reference to the foetus) may be termed the 

 posterior pole of that membrane, had extended into the non-impreg- 

 nated horn of the uterus. This point, however, in view of the 

 lacerated state of the membranes, it was manifestly impossible to 

 decide in the absence of another and more perfect specimen. At 

 the same time it is to be observed that the limitation of the chorionic 

 membrane to the impregnated uterine horn in the various species of 

 Carnivora previously examined, justifies the conclusion that in Procyon 

 that membrane does not extend into the unimpregnated horn, as 

 happens in the case of the Ruminants, Solipeds, and others. 



Allantois. — "With regard to the exact arrangement of this membrane, 

 owing to the rupture which had taken place, I am by no means 

 certain. At the same time I may state that, by means of careful dis- 

 section, I was able to detect a delicate membrane, which, although 

 closely applied to the fcetal surface of chorion, could be readily 

 detached from the non-placental area of the latter. This membrane, 

 which I regard as the allantois. was coextensive with, and formed a 

 lining to the uninjured pole of the chorion. At the margin of the 

 placenta, the allantois could be traced onwards as a distinct membrane, 

 which closely invested the fcetal surface of that organ. Moreover, an 

 examination of the shreds of the posterior chorionic pole showed that 

 here also the allantois could be detached in a fragmental form from 

 the fcetal surface of the former. I feel justified, therefore, in assuming 

 that, had the chorion been entire, the allantois would have been found 

 to be coextensive with and to have borne the same relation to it that 

 it bears in other Carnivora. I failed, however, to detect any prolonga- 

 tion of the allantoic sac along the umbilical cord, nor did I succeed 

 in isolating as a distinct membrane that portion of the allantois which 

 invests the outer surface of the amnion. 



Umbilical Vesicle. — Of this structure I could not distinguish the 

 slightest trace. Its absence in Procyon is remarkable in view of its 

 constant occurrence in other carnivorous mammals. 



-1- : 'lion. — -After removal of the foetus from the bag of the chorion, a 

 third membrane was exposed, the interpretation of which occasioned 

 considerable difficulty because of its peculiar relations to the other 

 membranes already described. The appearance of the membrane is 

 faithfully reproduced in fig. 2. The sac in question, when floated out in 

 spirit, presented an appearance not at all unlike the finger of a glove. 



