PLATE 3 



EXPLANATION OF PLATES 



9 Section through the closed intestine of a 4 mm. embryo. Note that two 

 germ cells have already left the intestinal entoderm. See corresponding sketch 

 (fig. 9a). 



10 and 106 Representing two detailed studies from the area indicated by the 

 rectangle in figure lOo. (Transverse cut through 6 mm. embryo.) Figure 10 

 shows a section through the germinal epithelium. Figure 10b represents a sec- 

 tion through the base of the mesentery. Note the enormous size of the germ 

 cells. 



11 Representing a section through the well developed indifferent gonad of 

 the 10 mm. embryo. The portion of the gonad is indicated by the letter g in 

 the corresponding sketch (fig. 11a). 



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