BEYOPHYTA— MUSOI 



lis 



spiral 



Fig. 873. 



lig. 



thickenings ; others, which form a network between the 

 ones, are small and tubular and contain ohloroplastids. 



The antheridia and arche- 

 gonia are usually borne amid 

 clusters of leaves at the apex of 

 a shoot. Most generally there 

 are several together, though this 

 is not always the case. Some- 

 times a shoot bears only an- 

 theridia, sometimes only arche- 

 gonia, sometimes archegonia in 

 the centre of the sorus or collec- 

 tion, and antheridia around the 

 periphery. We may thus have 

 monoecious, dioecious, or herma- 

 phrodite arrangement. 



The sorus is invested with 

 leaves of rather different cha- 

 racter from the ordmary foliage 



, Leaf of Sphagnum. A. Sur- 

 face view. E. Section. 



Fig. 874. 



^nt. 



Fig. 874. Apes of fertile shoot of Moss (Polytrichum) bearing antheridia, 

 ant, and paraphyses, par. I. Leaves of the shoot. 



leaves ; the innermost of them at any rate growing up in a sort 

 of perichffitial fashion round the base of the capsule as it begins 



T 2 



