THE GENERATIVE APPARATUS. 193 



it there. Traction is now made steadily and in the proper 

 direction ; and the assistant at the same time, by manipu- 

 lating the belly, facilitates the delivery of the bitch, which 

 should be in a standing position, not upon its back." 



The newly-born pup is from six to eight inches in length, 

 and its placental zone is remarkable for a green colour due 

 to chlorophyll. The principal other respect in which the 

 membranous appendages of the young differ from those of 

 the foal or calf is in the persistence of the umbilical vesicle 

 until birth with its considerableomphalo-mesenteric vessels. 

 This is another result of short gestation, also it has been 

 found that the bitch gives less nutriment in proportion to 

 her weight to the foetus in utero than any other of our 

 domesticated animals. 



Monstrous conditions of pups, although by no means 

 rare, are not often the cause of difficult parturition. The 

 irregularity in development and form generally appears 

 as excess in number of digits, deficiencies of digits or 

 limbs, absence of face, and other minor additions to, or 

 defects of, parts. The comparative infrequence of double 

 foetuses may depend on the several in a multiparous 

 animal occupying their respective divisions of the uterine 

 cavity, whereas in animals ordinarily uniparous twin progeny 

 lie together in the cavity of the womb. This explanation, 

 of course, would not suffice in the case of a double ovum. 

 It will be enough if we here notice two irregularities with 

 regard to the development and position of the foetus. 

 Moles or anidian monsters have been found by Rainard in 

 the uterus of the bitch, most frequently in the last dilata- 

 tion of one of the horns, rarely in both, " and sometimes 

 between two dilatations which contain living foetuses. 

 They are spheroidal, soft, irregular in shape, and look like 

 flesh ; they appear to be composed of fibres running in 

 every direction. In the dilatation of the horn containing 

 them, traces of a zonular uterine placenta have been 

 observed." They were considered embryos of checked or 

 perverted development. Extra-uterine Foetation. — A case 

 is on record in which a foetus, of which the skeleton only 

 seemed to remain, was found in the mesentery of a small 



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