284 PHARMACEUTICAL BOTANY 



SUBDIVISION II. MUSCI OR MOSSES 



Plants found on the ground, on rocks, trees and in running water. 

 Their life histories consist of two generations, gametophyte and 



FIG. 153. Sphagnum acutifolium, Ehrb. A, prothallus (pr), with a young leafy 

 branch just developing from it; B, portion of a leafy plant; a, male cones; ch, 

 female branches; C, male branch or cone, enlarged with a portion of the vegetative 

 branch adhering to its base; D, the same, with a portion of the leaves removed so 

 as to disclose the antheridia; E, antheridium discharging spores; F, a single sperm; 

 G, longitudinal section of a female branch, showing the -archegonia (ar); H, 

 longitudinal section through a sporogonium; sg l , the foot; PS, pseudopodium; c, 

 calyptra; sg, sporogonium, with dome of sporogenous tissue; ar, old neck of the 

 archegonium; J. Sphagnum squarrosum Pers. ; d, operculum; c, remains of calyp- 

 tra; qs, mature pseudopodium; ch, perichaetium. (Gager, from Schimper.) 



sporophyte similar to the liverworts but differ from liverworts, 

 generally, by the ever-present differentiation of the gametophyte 



