The placenta of the four‐eyed opossum (philander opossum)Philander opossum)

@article{Enders1969ThePO,
  title={The placenta of the four‐eyed opossum (philander opossum)Philander opossum)},
  author={Allen C. Enders and Robert K. Enders},
  journal={The Anatomical Record},
  year={1969},
  volume={165}
}
The placental membranes of the four‐eyed opossum were studied by light and electron microscopy. The individual fetuses in each uterus were surrounded by amnion, had allantoic sacs of approximately the same size as each fetus, and were situated in a common yolk sac cavity. The extent of the choriovitelline placenta was marked by a prominent sinus terminalis, and at this margin there was a region where the trophoblast cells penetrated folds of the endometrium. Elsewhere the choriovitelline… 

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The mammals of North America , The mammals of North America , مرکز فناوری اطلاعات و اطلاع رسانی کشاورزی