BRACHYTHECIACEAE 253 



Plants growing in mats, commonly on the ground, on 

 decaying logs or at the base of trees, more rarely on rocks; 

 bright green or somewhat yellowish-green; not very com- 

 mon; sometimes fruiting. 



Stems prostrate, irregularly branched; branches short, 

 usually }{ or }i inch long; erect or ascending; sometimes in 

 clusters. 



Leaves small, straight, wide-spreading, even when dry; 

 usually bright green. 



Seta /4-H inch long; reddish-brown. 



Capsule short-cylindrical, inclined; mature in autumn. 



Operculmn long-beaked. 



Range, Arctic America, Canada, and the northern United 

 States; Europe; Asia; Africa. 



Eurhynchium strigosum (Hoflm.) Bryol. Eur. is not 

 commonly found in our range, as the var. robustum 

 Roell is the form usually col- 

 lected. The general charac- 

 ter of the growth, prostrate 

 stems, with nufnerous short, 

 erect branches and small wide- 

 spreading leaves, somew^hat 



resembles that of Plagiothe- Eurhynchium strigosum 



var. robustum 



cium striatelliim (p. 242) and 



Brachythecium velutinum (p. 248), but the branches 

 of Eurhynchium are longer, often in clusters, and 

 the leaves are a brighter green. If the specimens 

 are fruited and the long beak of the operculum of 

 Eurhynchium can be seen, it is the best field-character. 

 The capsule is longer as a rule than in Brachythecium^ 



