HYPNACEAE 



237 



Plants growing in rather loose mats on the ground, 

 on rocks, and on decaying wood; yellowish-green to 

 dark green ; common ; fruit sometimes abundant. 



Stans prostrate, irreg- 

 ularly branched; rarely 

 some shoots are pin- 

 nate; branches unequal in 

 length and quite straight. 



Leaves straight, erect- 

 spreading, not much 

 changed when dry; yel- 

 lowish-green to dark 

 green. 



Seta 1-2 inches long; 

 reddish-brown. 



Capsule long-cylindrical, slender, only slightly curved 

 and inclined; mature in autumn. 



Operculum short-beaked. 



Range, Nova Scotia to Montana, south to Alabama and 

 Missouri; Europe; Asia. 



Stereodon U aldanianus 

 Branch enlarged. 



Stereodon Haldanianus (Grev.) Lindb. (11 yp- 

 nmn Haldanianum Grev.) is one of the commonest of 

 the pleurocarpous mosses. It is the only species of 

 Stereodon with straight, erect-spreading leaves. It so 

 closely resembles certain species of Brackythccium 

 (p. 244) that it cannot be distinguished except when 

 fruited; then, the long capsule is the distinguishing 

 characteristic in contrast with the short capsule of 

 Brachythecium. 



