176 



SEX IN MICROORGANISMS 



■■.'•.\ o 



Fig. O. Selected stages of the life cycles of (a) Spirillina vivipara, (b) Dis- 

 corhis patellifor?ms, and (c) Polystomella crispa, from Myers (1938), redrawn. 



Stages: 1, microsphaeric adult; 2, formation of megalosphaeric offspring; 3, asso- 

 ciation of megalosphaeric gamonts (a, b), no association (c); 4, production of 

 gametes which may be amoeboid (a) or flagellated (b, c); 5, new generation of 

 microsphaeric young produced by syngamy. 



