238 



THE UROGENITAL SYSTEM 



lymphocytes, and special cells of Hofbauer, the significance of which is not known. 

 Lymphatics are also present. The epithelium of the villi, as we have seen, is at 



J - 



■.rl 



i - r\ 



Uterine ves I 



Root of villus 



■Scrtional villi 



Spongy layer 



Muscular wall 

 of ulcrus 



Fig. 246. — Section through a normal placenta of seven months in situ (Minot). X 5. 



first composed of a layer of trophectoderm with the outHnes of its cuboidal cells 

 sharply defined (Fig. 248 A). This layer (of Langhans) forms and is covered by 

 a syncytium, the trophoderm. In the later months of pregnancy as the villi 



