The Sub-genus Brachythecium 



Brachythecium rivulare, Bruch, Ms. See Plate XXIV. 



Habit and habitat. Growing in dark or yellow-green mats 

 on rocks and stones about springs and in swamps of moun- 

 tainous woods. 



Namt. The specific name rivulare refers to the habit of 

 growing in wet places 



Portion of peristome with one outer tooth 

 on the right with annulus cells at its base, 

 two keeled and perforated inner teeth are 

 seen on the left with cilia between. 



(a) Spore-case 

 with lid showing 

 point; (6) spore- 

 case without lid. 



Branah-leaf. 



Brachythecium rivulare. 



Plants (gamefophyte). Woody, prostrate, naked, or with 

 rooting filaments, secondary stems ascending from old stems, 

 arched to 3 inches long, nearly free from branches below, 

 irregularly branching above. 



Leaves. Branch leaves erect spreading, oval to oval lance- 



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