2-43 p.m. 



2-50 p.m. 



Fig. 10 Volvox. A-I, stages in the development of the oospore of 

 V. rousseletii. A, zoospore just after escape. B, first division. F, pre- 

 paration for inversion. G-I, inversion. (All x 375.) J-O, stages in 

 the inversion of a sperm bundle of V. capensis. (AJl x 750.) (After 



Pocock.) 



32 



