578 



A TEXTBOOK OF THEORETICAL BOTANY 



Lycopodium Plant 



Strobilus 



Sporangium 



Antherozoids 



Spores 



Prothaltus 

 Fig. 587. — Life-cycle oi Lycopodium clavatum. 



Fig. 588. — SelagineUa kraussiatm showing prostrate habit and 

 rhizophores bearing roots. Half natural size. 



The stem is trailing, up to 30 cm. long and richly branched. Young 

 branches develop so quickly that they seem at first to be equal to the main 

 axis, thus giving an appearance of perfect dichotomy, which, however, is not 

 the case. The main apex has two, four-sided, apical cells, but the side 

 branches have only one, which is three-sided, and is formed from a segment 

 of one of the main apicals. They are thus truly lateral and the branching 

 is monopodial. The side shoots also branch freely in the same way, the 

 young branches all lying in the same plane and forming a flat, pinnate frond. 



