Volvox in South Africa. 



623 



FIG. 10. I'. Rousseletii. Development of the germ colony (continued). 



A-I, The same colony as in fig. 9; A, preparation for inversion; B-H, inversion; 

 I, fully formed germ colony, rotating within vesicle, cilia lengthening ; J, 

 optical section of an older germ colony still enclosed in the vesicle; K (from 

 a photograph), small portion of a fully developed Juvenile showing three 

 cells from the equatorial region and part of the developing daughter colony, 

 already inverted, with a gonidium. 



A-I x about 500; J x about 600; K x 875. 



