THE PEAT MOSSES 



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peat mosses arise from special buds. These cell plates suggest 

 the simple thalloid gametophytes of the liverworts, and the leafy 

 structure is perhaps a special development from them. 



The peat mosses live in bogs and swamps and are especially 

 common in northerly regions and in the mountains, where they 



FIG. 260. The sporophyte of the peat moss (Sphagnum) 



A, group of the sporophytes on stalks, which are really growths from the game- 

 tophyte. B, longitudinal section through a sporophyte, showing the large foot 

 imbedded in the top of the stalk : a, the remains of the parent archegonium, 

 with the neck still present ; s, spore chamber ; c, cover 



grow over wet rocks, sometimes covering large areas. They 

 frequently accompany certain sedges and shrubs that grow 

 inward from the margins of ponds over the surface of the 

 water, which finally becomes covered with a mat of floating 

 vegetation. Such growths produce soft or quaking bogs, for the 

 surface is not firm enough to hold any large animal which 

 might walk upon it. Quaking bogs become firmer as the lower 



