438 



BOTANY 



]'ai;t n 



archegonia arise on different plants. The arcliegonia and antberidia 

 of Mosses differ in their development from those of other Archegoniatae 



/"S\ 



Fio. 37;i. — Andreaea pc.trophUa. ps, Pseudopodium ; 

 Spf, foot ; 7c, capsule ; r, calyptra. ( x 12.) 



\ 



1 ^ :^' ^r% 



r-'^/M 



^/ 



rh 



Fig. 380. — Ephoiurum seii-atuin. p, Protoneiiia ; 

 b, foliage-leaf ; .f, sporogoniuni ; c, calyptra ; 

 rh, rhizoids. (After W. P. Schimper, x 200.) 



Fio. 3sl. — rolytrichum commune, rh, Rlii- 

 zoids; s, seta ; c, calyptra ; ap, apophysis ; 

 (1, operculuiii. (Nat. size) 



by being formed by the segmentation of a two- or three-sided apical 

 cell. 



The SI'OROGONIUM of the Mosses (^^") develops a capsule with an 

 axial COLUMELLA consisting of sterile tissue (Fig. 385). The si)ore-sac 

 surrounds the columella, which accumulates food material and water 

 for the developing spores. Elaters are never formed. In the young 



( 



