LIFE HISTORY OF A MOSS 



197 



appendage composed of starch, which ultimately drops 

 off. It will be seen at once that the sperms of sphagnum 

 differ from those of ferns in having only two cilia instead 

 of many. When the antheridium is ripe the cells swell, 

 and the capsule is thus forced open. 



Fig. 142. — Sphagnum. Photomicrograph of a longitudinal section of an 

 antheridial branch, showing five antheridia. (Cf. Fig. 143.) 



181. Archegonial Branches. — The female branches, or 

 archegoniophoreSy usually occur near the upper end of 

 the plant, and bear the archegonia at their tips. As in 

 the case of the fern, each archegonium consists of a 

 neck (slightly twisted in Sphagnum), with neck-canal, a 

 venter, containing the egg, and a basal stalk, or pedicle, 

 not found in the ferns. Several archegonia commonly 



