658 



J. T. PATTERSON 



n- 



27 



28 



Fig. 27 A section through g to h of figure 29. The buds of Embryos I and II 

 are shown in section. The enlargement of the cavity (marked Cay.) lying below 

 and to the left of the extraembryonic cavity is an artifact, caused by the lifting up 

 of the Trager epithelium from the mucosa. X 79. 



Fig. 28 Sketch of the blastocyst No. 175, showing the four embryonic rudi- 

 ments. X 14.5. 



Fig. 29 Diagram of the same specimen. The broken parallel lines show the 

 planes of the sections illustrated in plate 10. X 29. 



