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HOW TO KNOW THE MOSSES 



73. PLAGIOTHECIUM Bryol. Eur. 

 (Pla-gi-o-the-ci-um) 



A genus of many species, only three of which are 

 given below. Name derived from the Greek for 

 " oblique " and a " little vessel," referring to the 

 capsule. 



a. Leaves flattened, apparently in two opposite rows 



.... P. denticulatum, 

 P. sylvaticum. 

 h. Leaves wide-spreading, equally arranged around stem 



.... P. striatellum. 



Plants growing in flattened mats on earth, rocks, and de- 

 caying logs in woods; light or yellowish-green; often glossy; 



very common; fruit frequent. 

 Stems prostrate^ irregularly 

 branched; branches flattened, 

 broad. 



Leaves straight, large, wide- 

 spreading, flattened, appar- 

 ently in two opposite rows; 

 light or yellowish-green; often 

 somewhat glossy. 

 Seta, i-i/^ inches long; reddish-brown. 

 Capsule long-cylindrical, inclined, curved; mature in 

 summer. 



Operculum cone-shaped or short-beaked. 

 Range, almost cosmopolitan in temperate and cooler 

 regions. 



Plagiothecium denticidatum 

 Portion of branch enlarged. 



