. On the anatomy of vertebrates [electronic resource] . receiving ramifications of the allantoicvessels. The umbilical cord, one-third of an inch in length, goesto one of the cotyledons, whence the vessels extend to the omphalo-mesentericduct expands into a py-riform vitellicle, five linesin length. The Ferretproduces from five toeight young; she hasusually eight teats; hasa six-weeks gestation,and produces twice ayear. In the Martensthe placenta is undivi-ded (Mustela rnartes, M. foina, &c.); the decidua serotinasinks into its substance along a narrow tract at the middle of theouter
. On the anatomy of vertebrates [electronic resource] . receiving ramifications of the allantoicvessels. The umbilical cord, one-third of an inch in length, goesto one of the cotyledons, whence the vessels extend to the omphalo-mesentericduct expands into a py-riform vitellicle, five linesin length. The Ferretproduces from five toeight young; she hasusually eight teats; hasa six-weeks gestation,and produces twice ayear. In the Martensthe placenta is undivi-ded (Mustela rnartes, M. foina, &c.); the decidua serotinasinks into its substance along a narrow tract at the middle of theouter surface of the zone, as in the Elephant: they bring forth,commonly, twice a year, but are less prolific than the navel-string is very short: the allantois is more elongated;a trace of vitellicle may be seen in a small bilobed yellowishpatch, upon the inner surface of the placenta, where the navel-string ends. In the Hyaena the deciduous substance becomes fused withthe chorionic placental processes: it is moderately thick, spongy, 579. Fcetus and Placenta. Puiorius Faro. cxxn. DEVELOPMENT OF QUADRUMAN-A. toniatose, non-coherent: the foetal processes penetrate cavities inthe decidua apparently homologous with the utriculi of thehuman uterine lining, and having as little the structure of truefollicular glands. The original deciduous capsule of the ovum isreduced to a very thin layer of mucous substance, exterior tothe placental zone. Seals have rarely more than two young, and more commonlybut one, at a birth. In the latter case the foetus and its mem-branes are limited to one horn of the uterus, not extending intothe opposite horn, as in Cetacea. The placenta is zonular, infour or five continuous or connected divisions. In Phoca vitulinathe diameter of the zone parallel with the long axis of the ovumis between two and three inches. In parturition the scleroustissue of the symphysis pubis becomes relaxed, allowing divarica^tion of that part of the pelvic arch, whi
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