IQ8 
STRUCTURE AND LIFE HISTORIES 
FIG. 143. 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, an- 
theridium discharging spores; F, a single sperm; G, longitudinal section 
of a female branch, showing the archegonia (ar); H, longitudinal section 
through a sporogonium; sg 1 , the foot; ps, pseudopodium; c, calyptra; sg, 
sporogonium, with dome of sporogenous tissue; ar, old neck of the arche- 
gonium; /. Sphagnum squarrosum Pers.; d, operculum; c, remains of calyp- 
tra; qs, mature pseudopodium; ch, perichaetium. (Cf. Figs. 139 and 142.) 
(From Schimper.) 
