Development of 4he Mammal 303 



caduca. That part of the decidua to which 

 the ovum becomes attached (Fig. 98) is called 

 the decidua serotina ; the part that is reflected 



FIG. 98. SEMI-DIAGRAMMATIC OUTLINE OF AN 

 ANTERO-POSTERIOR SECTION OF A HUMAN UTERUS 

 CONTAINING AN EMBRYO OF ABOUT FIVE WEEKS. 

 (From Minot, after Allan Thompson.) 



, anterior surface, ch, chorion, within which is the 

 embryo enclosed by the amnion, and attached to the chorion 

 by the umbilical cord from the cord hangs the pedunculate 

 yolk-sac. ^, outer limit of the decidua. /, posterior 

 surface, rr^ decidua reflexa. jj, limits of the decidua 

 serotina. 



