FERTILIZATION 



259 



B 



D 



E 



G 



H 



Fig. 171. — Diagram of the nuclear changes during endomixis in Parame- 

 cium aurelia. A, typical nuclear condition; B, degeneration of macronucleus 

 and first division of micronuclei; C, second division of micronuclei; D, degener- 

 ation of six of the eight micronuclei; E, division of the cell; F, first reconstruction 

 micronuclear division; G, second reconstruction micronuclear division; H, 

 transformation of two micronuclei into macronuclei; I, micronuclear and cell 

 division; J, typical nuclear condition restored. 



