A3. 



FIG. 1. Vohox membranes, stained with methylene blue. 

 A, V. aureus. B, V. a/ricanus. C, V. capensis sp. nov. and V. Rousseletii. 



In each : 1, Optical section of whole colony. 



2, A small portion further enlarged. 



3, Cells in surface view. 



In V. aureus the central star-shaped mass stains deep purple: in T . cipcnsis 

 the mucilaginous content of the hollow sphere stains slightly lighter purple. In 

 V. africanus the inner membrane is regular and clearly defined when the colony 

 is young, later becomes displaced and distorted by the developing daughter 

 colonies. A 1( B 1; C x x 60 ; A 2 x 100 ; others x 500 (roughly). 



