Plate 12 



Figs. 1-4. Stigeoclonium pachydermum Prescott: 1, x 100; 2, x 

 500; 3 and 4, x 250 



Figs. 5-8. Splmeroplea annulina (Roth) C. A. Agardh: 5, portion 

 of vegetative cell, x 650; 6 and 7, germlings, x 325; 8, 

 portion of oogonial cell, x 650 ( after Smith, courtesy 

 McGraw-Hill Co.) 



Figs. 9, 10. Stigeoclonium pachydermum Prescott: forms of branch- 

 es, X 250 



[684] 



