THE FETAL MEMBRANES AND PLACENTATION OF THE TROPICAL AMERICAN VAMPIRE BAT DESMODUS ROTUNDUS MURINUS

Abstract

Completely interstitial implantation occurs in the markedly progestational endometrium. A unilaminar blastocyst with possible early endoderm and mesoderm was found in the tube. Important features are antimesometrial implantation and embryonic disc; amnion by cavitation; incomplete inversion of yolk sac with conspicuous Reichert''s membrane; allantois rudimentary; chorio-allantoic placenta antimesometrial, discoid, labyrinthine, endotheliochorial; no accessory placenta; decidua capsularis complete but disappears later; decidua basalis thick but nearly disappears by term; no parietal decidua but parietal endometrium largely destroyed by term. The similarity of this desmodontid to the Phyllostomatidae is great, suggesting a relatively close relationship between the 2 groups. Only uteri from the latter half of gestation were used for histochemical study. Ribonucleic acid occurs in greatest amount in the syntrophoblast, but is also appreciable in the cytotrophoblast and yolksac endoderm. Glycogen is restricted to the decidua basalis and the mesothelium of the vitelline splanchnopleure. Glycoproteins are widely distributed. Alkaline phosphatase was found only in the uterine epithelium adjacent to the placenta, and in the walls of the maternal tubules of the labyrinth.