PLATE 50 



Chlanidophora abyssicola S. and G. 

 Fig. 1. Two specimens of mature plants. Natural size. 



Fig. 2. Young aplanosporangium in the distromatic portion of the frond. 

 The two small cells below represent cross-sections of hairs. 



Fig. 3. Cross-section showing three mature aplanosporangia with numerous 

 aplanospores and two paraphyses. 



Fig. 4. Surface view of a portion of the growing margins of a frond show- 

 ing the method of cell division. 



Fig. 5. Portions of four cross-sections showing the character of the cells in 

 different parts of the frond. The upper is the younger, near the growing margin. 

 The others are successively older toward the base. 



Fig. 6. Longitudinal section through the margins. 



Fig. 7. Longitudinal section in the older part of the frond showing the 

 origin and prostrate position of hairs. Figures 2-7. X 250. 



Phaeostrophion irregulare S. and G. 

 Fig. 8. Cross-section of the frond with zoosporangia. X 250. 



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