THE GREAT GKOUPS OF BRYOPHYTES 



117 



Fig. 100. Species of Lepidozia. a geiras of leafy liverworts, showing different leaf 

 forms, and in A and C the dehiscence of the sporogonium by four valves. In C 

 rhizoids are evident; and in B, D, and E the three rows of leaves are seen, the 

 leaves of the ventral row being comparatively small. — After Engler and Prantl. 



Mosses, and possibly to the Pteridophytes also. The 

 thallus is very simple, being differentiated neither in 

 structure nor form, as in the two other lines ; but the 



