PLATE 51 



Ectocarpus socialis S. and G. 



Fig. 12. Small group of plants showing rhizoids, a few cells with chro- 

 matophores, and the positions and shapes of the zoosporangia. X 125. 



Fig. 13. Selection of parts of filaments showing the positions and relative 

 shapes and sizes of the gametangia. X 125. 



Ectocarpus cylindricus f. codiopMlus S. and G. 



Fig. 14. Group of young plants showing both zoosporangia and game- 

 tangia, the two parts of ramuli on the left representing these organs on the 

 same plant. X 60. 



Ectocarpus Taoniae S. and G. 



Fig. 15. Portion of a creeping filament showing erect filaments and the 

 positions and relative shapes and sizes of the gametangia on both the creeping 

 and the erect filaments. X 250. 



Ectocarpus afflnis S. and G. 

 Fig. 16. Diagrammatic representation of a small group of plants on their host. 

 Fig. 17. Portions of filaments illustrating positions, relative shapes and 

 sizes of gametangia. X 225. 



This plate is a reprint of Setchell and Gardner, Univ. Calif. Publ. Bot., vol. 7, 

 p. 420, pi. 46, 1922. 



[774] 



