THE GEEAT GKOUPS OF BKYOPIIYTES 



121 



(Fig. 102), the thallus part dying. Sometimes, however, 

 the filamentous protonema is very persistent, and gives rise 

 to a perennial succession of leafy branches. 



.P 



Fig. 103. Tip of leafy branch of a moss {Fiinana), bearing a cluster of sex organs, 

 showing an old anttieridium {A), a younger one (i?), some of the curious associated 

 hairs (p), and leaf sections (Z).— After Campbell. 



At the summit of the leafy gametophore, either upon 

 the main axis or upon a lateral branch, the antheridia and 

 archegonia are borne (Figs. 83, 103). Often the leaves at 

 the summit become modified in form and arranged to form 



