PLATE 43 



Zonaria Farlowii S. and G. 



Fig. 63. Habit sketch indicating parallel and radiating lines of cells. 

 Diagrammatic. 



Leathesia amplissima S. and G. 



Fig. 64. Section perpendicular to the surface of the frond showing the 

 characters of the cells, hairs, paraphyses, and zoosporangia. X 250. 



Leathesia difformis (L.) Aresch. 



Fig. 65. Section perpendicular to the surface of the frond showing the 

 characters of the cells, hairs, paraphyses, and gametangia. X 250. 



Fig. 66. Section perpendicular to the surface of the frond showing the 

 character of the cells, zoosporangia, gametangia, hairs, and paraphyses X 250. 



Leathesia nana S. and G. 



Fig. 67. Section through the frond perpendicular to the surface showing 

 the character of a few filaments bearing hairs, gametangia, and paraphyses. 

 X 125. 



[758] 



