OLIGONEPHRIDIA 



261 



the yolk-cell syncitium (yc) which then covers the mycetom like a cap 

 (Fig. 185) and eventually becomes an envelope (Fig. 186). If, on the 

 other hand, the blastoderm is closed, the mycetom anlage in its outward 



Fig. 184. — Aphis sam- 

 huci. Blastoderm. After 

 the eighth division, imyct) 

 Mycetoblasts. 



myct 



Fig. 185. — Hyadaphis sp. 

 Blastoderm. Anlage of my- 

 cetom. (bid) Blastoderm. 

 ifol) Egg follicle, (myct) 

 Mycetom. (yc) Yolk-cell 

 syncitium. 



myct 



Fig. 186. — Doralis fahae. 



{hid) Blastoderm, {myct) Mycetom. 



{ycc) Yolk-ceil cap. 



growth pushes the blastoderm cells aside to effect an opening. Thus the 

 end result is the same in establishing a connection between the mycetom 

 plasma and the egg follicle (Fig. 186). 



