PS1LOTACEAE 31 



1. PSILOTUM R. Br. 



Tufted, epiphytic or terrestrial, but humus-loving, 

 sometimes stiff plants, with slender coral-like roots. 

 Stems repeatedly dichotomous. Leaves alternate, remote, 

 reduced to scales. Sporangia 3-celled, 3-lobed, opening 

 by 3 valves at the apex, closely sessile. Spores mealy, 

 oval or elongate-reniform in outline. Represented by 2 

 or 3 species of wide geographic distribution. 



1. P. nudum (L.) Griseb. Stems tufted, erect or 

 nodding, rather rigid and tough, 1-4.5 dm. tall, 3 -angled, 

 forked, sometimes copiously 

 so above, the branches with 

 3 wing-like angles: leaves 

 remote, scale-like or awl- 

 like, 1-1.5 mm. long: spo- 

 rangia in much-interrupted 

 spikes, 2-2.5 mm. wide, usu- 

 ally wider than long, the 

 three lobes rounded, yellow 

 or yellowish-brown. Ham- 

 mocks. Figure 18, reduced. 



This relative of the club- 

 mosses is not uncommon in 

 most of the nearby pineland 

 hammocks. It grows on the 

 bark in partly decayed spots 

 on standing hardwood trees and on palmettos, particu- 

 larly near the bases of the trees. It occurs commonly 

 on fallen and partly decayed trunks and on the ground 

 where tree-trunks have decayed and fallen to pieces. 

 The coral-like roots are securely fastened in the sub- 

 stance in which they grow. The plant is rather rare in 

 Royal Palm Hammock, while in some of the hammocks 

 not far distant on Long Key it is exceedingly plentiful. 



