A Morphological Study on the Development of the Placenta of the Golden Hamster (Mesocricetus auratus)

Golden Hamster (Mesocricetus auratus) 의 태반형성(胎盤形成)에 관한 형태학적(形態學的) 연구(硏究)

The placentation in the golden hamster (Mesocricetus auratus) and the morphological changes occuring in its placenta from implantation to parturition have been observed by light microscope. The results obtained were summarized as follows. 1. The development of the placenta in the fertilized ovum implanted on the day 5 of gestation was described with increasing gestational age. 2. On the day 8 of gestation, the chorioallantoic placenta was formed by fusion of the allantois to the chorion of ectoplacental cone. 3. On the day 13 of gestation, Reichert's membrane with the parietal yolk sac disappeared in a circumscribed area antimesometrially.