Mosses and Lichens 



spreading or recurved ; -veins two, and short ; cells long and 

 narrow ; spore-case short, broadly ovate, horizontal. 



Leaf. 



Spore-cases. 

 Hylocomnium: Hypnum triquetrum. 



THE CEDAR MOSSES 



HYPNUM: Sub-genus THUIDIUM, Schimp. 



The species of this sub-genus are fern-like and grow in 

 dense flat mats on decaying wood. 



The generic name is derived from the Greek Ova, or 0via, an 

 ancient name for some resinous-bearing evergreen. The moss 

 was so called by Wm. Philipp Schimper, from its resemblance 



to a tiny cedar tree. 



The primary stems are densely 

 covered with rootlets, and the sec- 

 ondary are i to 3 times pinnately 

 branching. The leaves 

 on the stem are tri- 

 angular heart-shaped 

 with a strong vein, a 

 more or less long- 

 pointed apex, and a 

 base extending down- 

 ward on the stem ; 

 papillae are found on 

 one or both faces ; 

 leaf-'ike organs (para- 



Vertical section 

 of peristome show- 

 ing three cells of 

 the annulus and an 

 Inner and outer Spore-case 

 tooth. without lid. 



Spore-cases with 

 lids. 



Thuidium delicatulum. 



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