PTERIDOPHYTA 



A. LYCOPODIN^E 



I. Heterosporous Type 



SELAGINELLA MARTENSII 



SPOROPHYTE 



I. In a well-grown plant note with the naked eye the 

 following external characters : 



1. The stem ascending, frequently branched, appar- 

 ently in a dichotomous, but really in a monopodial 

 manner (see p. 270) : the branching occurs only in a 

 single plane. 



2. The leaves, of small size, and simple in form, 

 with a ciliate margin, and arranged in alternating pairs : 

 each pair consists of a dorsal and a ventral leaf, the 

 whole series thus forming four orthostichies : note 

 the two different sizes of leaves 



a. The larger ventral leaves, arranged in two 

 orthostichies, and without terminal awns. 



I. The smaller dorsal leaves, also arranged in two 

 orthostichies, each leaf being terminated by a fine 

 awn. 



