REPRODUCTION AND DEVELOPMENT IN CHORDATES 



Fig. 5.25. .4, chorionic vesicle of man removed from uterus, showing vilh on surface; age, 

 about 34 days. B, chorionic vesicle of man, opened to show embryo enclosed by amnion 

 and attached to placenta at lower right; crown-rump length of embryo, 17.6 mm.; age, about 

 7 weeks. (Photographs courtesy Carnegie Institution of Washington, Department of Embryology.) 



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