CHAPTER VI 



The Maturation of the Germ-cells (continued): 



The Maturation of the Egg and the Nature 

 of the Meiotlc Phase 



IN the account of the maturation of the germ-cells given 

 hitherto attention has been confined to the phenomena 

 as seen in the development of the spermatozoon, since in 

 the majority of animals they are more easily followed in 



FIG. 8. Three types of Insect ovarian tubes. 

 (After KORSCHELT and HEIDER.) 



Above. Orthopteran type, without nutritive chambers. 

 Middle. Coleopteran or Hymenopteran type, nutritive 



chambers alternating with ova. 

 Below. Hemipteran type, single large nutritive chamber 



connected with ova by ducts. 



the male than in the female. In the development of the egg, 

 however, the process is exactly analogous, differing only in 

 those features which depend on the inevitable difference 

 between the production of the minute, active spermatozoon 

 and the relatively large, inert, and often yolk-laden egg. 



