PLATE 4 



Placoma violacea S. and G. 



Fig. 1. Habit sketch of the thallus. X 75. 



Fig. 2. Perpendicular section through young confluent thallus, showing the 



more or less radial arrangement of the cells. X 250. 



Fig. 3. Surface view of a group of cells. X 375. 



Dermocarpa protea S. and G. 



Fig. 4. A series of gonidangia illustrating different shapes and sizes. X 250. 

 Fig. 5. A group of cells showing various stages of gonidial formation. 

 X 250. 



Anacystis ela1)ens (Kuetz.) S. and G. 



Fig. 0. Surface view of a colony, showing tendency to break up into groups 

 of cells. X 125. ■ 



Fig. 7. A single group of cells from the colony. X 500. 



Xenococcus Cladophorae (Tilden) S. and G. 



Fig. 8. A group of vegetative cells in various stages of growth ami inter- 

 spersed gonidangia. X 250. 



Pleurocapsa entopliysaloides S. and G. 



Fig. 9. a-g, A series of vegetative cells in various stages of development; 

 h-i, two gonidangia. X 250. 



Fig. 10. Section view through a large colony showing the somewhat ento- 

 physaloid arrangement of groups of cells. X 250. 



This plate is a reprint of Gardner, Univ. Calif. Publ. Bot., vol. 6, p. 480, pi. 38. 

 1918. 



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