THE PLACENTA. 



91 



from 4 to 6-lOths of an inch, \Yhich arc received into the depressions of 

 the maternal cotyledons. This ramifying or racemose disposition of the 

 chorial villi is peculiar to the Bovine and Ovine species. The chorial 

 cotyledons are attached to the chorion by a very short, thick and 

 vascular pedicle ; between them and the maternal cotyledons there is 

 always to be found a small quantity of thick, white, milky-looking fluid 

 — the so-called " cotyledonous " or " uterine milk." 



According to Schlossberger, this uterine milk should be considered as 

 a fluid analogous to milk or chyle. It contains 88 per cent, of water, 

 To of fat, 0-7 of salts, and 9-6 of a protein substance. In the cotyledonal 

 fluid, as well as in that on the surface of the uterine mucous membrane 

 of a Mare towards the end of pregnancy, Ercolani has demonstrated 

 the presence of albumin ; in the same fluid he has also proved the exist- 

 ence of amidon, dextrin, and sodium chloride. ^ 



COTTLKDON OK A Cow's UtERUS. 



a a. Surface of F(ftal Chorion ; h h, lilood vessels of Fn^tal Chorion ; r r. Surface 

 of I'terine Mucous Membrane ; it d, Bloodvessels of ditto ; /, Secretion from 

 T'tricuKy (Jlands— Cotyledonous Milk— l>ftw.en Maternal and Futal Vessel.-, 

 and which is necessary to the Mutual Interchange of liases, and Nutrient, 

 Effete, and other Matters between Parent and Offspring. 



The reticulated surface of the maternal cotyledons is homologous with 

 the decuhia scrotina of other mammals; but it possesses a flrmer texture, 

 and usually remains attached until the termination of gestation- -allow- 

 ing the fa-tal villi to be withdrawn from it at birth ; it is afterwards 



' We must not overlook the fact, that the txistence of the "uterine milk" in the 

 living pregnant animal has been denied by M. Colin (Trailv de Phi/Mioloi/if Comparce 

 rff.i Aiiiniaiix, 1872, vol. ii., p S70), who states that this fluid is simplv a product of 

 cadaveric decomposition, and is not found during life ; a.s he h.xs a«.sure<i himself in the 

 most evident manner, by opening the uterus of a pregnant Mare and Cow. It is not 

 found immediately after death, as he has demonstrated on many occasions in Cows an<l 

 Sheep slaughtered in the abattoirs at all j)eriods of gestation ; it is not even observed 

 after six, twelve, or twenty-four hours, or longer, when the surrounding temperature does 

 not favour decomposition. It is only when the placentie sp<>ntaneotisly separate, or are 

 disunited by slight traction, at a greater or le.ss time after death, accurdini; to circum- 

 stances, that the white or yellowisn-red coloured fluid appears between the chorion and 

 uterine mucous membrane. In proportiiui as decomposition has advanced, the fluid is 

 abundant. Colin therefore concludes that it is a product of softening and progressive 

 dissolution of the uterine mucous membrane and its cotyledons, as well as the placentse 

 themselves. 



