468 



MOSSES AND FERNS 



CHAP. 



the " protocorm." This is a tuber-like organ (Fig. 244, T>, pcj, 

 from which the leaves and stem apex are subsequently 

 developed. The cotyledon arises from the summit of the 



Fig. 245. — Erabryogeny of Lycopodium phlegmaria (L.) (after Treub). st. Stem ; cot, cotyledon ; 

 susp, suspensor. A, X31S; B, X235; C, X235; D, X175. 



protocorm, and is followed by a number of secondary leaves 

 which form successively from a group of meristematic cells, 

 which usually develop into the permanent apex of the stem. 



