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Show 1881.] VAGINAL APPARATUS IN THE MACR0PODIL\E. 977 Though several anatomists have met with uterine foetuses in situ, no one as yet seems to have had the good fortune to find an embryo in any part of the vaginae ; consequently there has been much controversy as to the route taken by the embryo in passing to the urogenital passage. Some writers maintain that it comes down one of the lateral canals ; while others affirm that these serve only for the conveyance of the semen, and that the embrj'o passes directly from the median vaginal canal into the urogenital chamber. W e have ventured to bring the subject under the notice of the Society for several reasons. First, because we have found the open condition in some species in which it has not hitherto been recorded ; secondly, because the text-books used by students in this country either refer to the subject only very briefly, as in Prof. Owen's ' Comparative Anatomy,' vol. iii., or nor at all, as in the manuals of Profs. Gegenbauer, Huxley, and Macalister ; thirdly, because, with the exception of H o m e and Owen, no English observers seem to have noticed the open condition of the median cul-de-sac, while it has, as we shall show presently, attracted the attention of a considerable number of continental investigators. As will be pointed out later on, many of the observations already recorded are almost valueless, because the observers have not referred their specimens to any genera or species, or because they have been unable or have neglected to offer any evidence as to whether the animals they are dealing with had certainly produced young or not. Before giving the details in connection with our specimen, it will be interesting to state briefly the results already obtained. As far as we can learn, the observers who have investigated the condition of the median vaginal canal, and have published the results arrived at, are the following-Home, Cuvier, Seiler, G. St.-Hilaire, Owen, Carus, Vrolik, Poelman, Alix, Luca, Pagenstecher, Garrod, and Brass. Sir E. Home1, who published an account in 1785, seems to have been the first to give a description of the female reproductive organs of the Kangaroo. This writer says that impregnated uteri had reached John Hunter before his death, but that from want of leisure the illustrious anatomist was prevented from giving them the attention they deserved. Home does not say how many specimens came under his own observation, nor to what species they belonged. In one of his specimens he found the median vaginal portion (uterus of Home) a veritable cul-de-sac. In another specimen he found the median va°*inal portion (uterus of Home) in communication, by a small aperture, with the urogenital chamber (vagina of Home). Finding what he took to be an embryo in the median vaginal canal (uterus of Home), he supposed that he was dealing in this case with an impregnated uterus, aud in the previous case with one in the virgin condition; and he came to the conclusion that the median vaginal portion was impervious in the virgin state, that during pregnancy 1 Phil. Trans, lxxxv. 1785, pp. 222-230; also Lect. on Comp. Anat. vol. iii. pp. 341-370. PROC. ZOOL. Soc-1881, No. LXIII. 63 |