Peat-Mosses 



spreading, ovate to lance-shaped and usually have their surface 



covered with projecting points. 



The terminal oval spore-cases are immersed among the leaves 



before maturity, but later are protruded by the elongation of the 



cellular sheath (vaginule) surrounding the base of the spore-case. 



This is known as a false pedicel (pseudo- 

 podium). There is no lid, as the case 

 opens by splitting perpendicularly into 

 four or rarely six equal segments 

 which cohere at the apex. There are, 



Veil. 



Fertile plant. 



A sporophyte 

 separated from 

 the cellular 

 sheath. 

 Andrccea Hartmanii. 



Sterile plant. 



of course, no teeth when there is no lid. The small spores are 

 at first coherent in fours, later, when the case splits into valves, 

 they are disseminated by the wind, if the weather is dry; if it is 

 damp, the valves draw together to protect the spores. 



There are about one hundred species known at present, six 

 or more of them occurring in North America. The specific char- 

 acters are drawn mainly from the leaves. 



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