414 



H. H. Newman and J. T. Patterson. 



11 



FIG. 10. Cross section of scale-like villi, v., of the vesicle in fig. 14. The Trager 

 knots are still covered with a thin epithelium. The epithelium of the villi has 

 become a syncytium. The mesoderm has proliferated cells which have invaded 

 the villi, but as yet blood formation has not taken place. X 265. 



FIG. 11. The tip of a villus from a more advanced stage, showing, in addition to 

 the features described in preceding. figure, the well developed blood vessels, b.v. 

 X 265. 



