THE PLACENTA IN SITU. 



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FIG. 234. HUMAN PLACENTA IN SITU, ABOUT SEVEN MONTHS. VERTICAL SECTION. 



Am, Amnion. Cho, Chorion. Vi, Villous trunk, vi, Sections of villi in the substance of the placenta. D',D", 

 Decidua serotina. Me, Muscularis. Ve, Uterine artery, opening into the placenta; the fetal blood-vessels are 

 drawn black; the maternal blood-vessels are white; the chorionic tissue is stippled, except the canalized fibrin, 

 which is shaded by lines. The remnants of the gland cavities in the decidua are stippled dark. X 6 diams. 



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