CHAPTER XIV. 



LYCOPODIALES. 



The recent members of the Lycopodiales are considered 

 apart from the extinct genera in order that our examination of 

 the latter may be facilitated by a knowledge of the salient 

 characteristics of the surviving types of this important section 

 of the Pteridophyta. A general acquaintance with the extinct as 

 well as with the recent genera will enable us to appreciate the 

 contrasts between the living and the fossil forms and to realise 

 the prominent position occupied by this group in the Palaeozoic 

 period, a position in striking contrast to the part played by 

 the diminutive survivors in the vegetation of the present day. 

 In the account of the recent genera special attention is drawn 

 to such features as afford a clue to the interpretation of the 

 fossils, and the point of view adopted, which at times may 

 appear to lead to an excessive attention to details, is necessarily 

 somewhat different from that represented in botanical text- 

 books'. 



A. HOMOSPOREAE. 

 Lycopodiaceae : genera Phylloglossum, Lycopodium. 



B. HETEROSPOREAE. 



Selaginellaceae : genus Selaginella. 

 Isoetaceae: genus Isoetes. 



The existing plants included in the Lycopodiales are in 

 nearly all cases perennial herbaceous pteridophytes, exhibiting 



^ For a general account of recent Lycopodiales see Pritzel (02) ; Campbell (05) ; 

 Bower (08). 



