THE GKEAT GROUPS OF BEYOPHYTES 



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Fig. 100. Species of Lepidozia, a genus 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 Frantl. 



Mosses, and possibly to the Pteridopbytes also. The 

 thallus is very simple, being differentiated neither in 

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

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