646 Annals of the South African Museum. 



PIG. 



H-J. Young germ colonies (" Juveniles ") showing stages in development. 



H. Still within vesicle, cells separating (478). x 500. 



I. Elongated Juvenile recently escaped from vesicle ; gonidia undivided (475). 



x410. 



J. Rounded Juvenile, about the same stage, fewer celled (476). x 410. 

 K. Older Juvenile, '2 daughters in early stages of cell-division (534). x 240. 

 L. Few-celled Juvenile, 1 developing daughter. Fixed, osmic acid (538). x 260. 



PLATE XLVIII. 



Juvenile colonies. 



A-D. V. Rousseletii. From oospore cultures. 



A. Young Juvenile with 3 gonidia in early stages of cell-division. Top focus. 



Killed, osmic acid (483). x 280. 



B. The same, median focus showing eyespot and cilia (488). x 500. 



C. Typical well-developed Juvenile with a single daughter in an advanced stage 



of cell-division. Killed, osmic acid (540). x 350. 



D. Juvenile with 2 daughters nearly ready for inversion. Killed, formalin (536). 



x 260. 



E, F. V. capensis. 



E. Juvenile, first discovered, from Ackerman's Vlei, May 1931. ~)ne mature 



daughter nearly ready to escape. Top focus (358). 



F. The same, median focus, showing gonidia and cilia of daughter col my, vesicle 



wall, and inner wall of parent (360). Both x 228. 



PLATE XLIX. 

 Juveniles and second generation. 



V. capensis. 



A. Group from Ackerman's Vlei, showing two Juvenile colonies each with a 



single nearly mature daughter (upper one showing gonidia) and colonies of 

 the second and third generations. Killed, iodine (355). x 57. 



B. Undivided gonidium from a Juvenile containing in addition 2 developing 



daughters (363). x 1000. 



V. Rousseletii. From oospore cultures. 



C. Mature Juvenile from which daughter has escaped, showing pore of escape 



with torn edges (518). x 170. 



D. Daughter (second generation) escaped from above (517). x310. 



E. Colony of the second generation further advanced, showing 4 developing 



daughters and 2 abortive gonidia (533). Compare with PI. XIII, C; 

 XVII, A; XX, A. x78. 



F. Cell detail, anterior region of a younger second generation colony (352). 



x 1000. 



G. The same, from the posterior region, showing closer spacing of cells (534). 



x 1000. 



