SECT. VTI. BOG MOSS. 



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The common bog moss grows so rapidly that, rootless 

 as it is, it soon covers a pool with its matted bundles 

 of branches, and as in a few years it has no room to 

 spread, the lower stems and branches decay, sink to 

 the bottom, and begin to form a peat moss, while the 

 upper parts grow on, so that new stems and branches 

 are perpetually produced. Multitudes of spores no 

 doubt germinate, and, in this way, the pool is filled up, 

 and a peat moss is at length formed. 



The Sphagnum moss has such a power of absorbing 

 moisture from the atmosphere, that it forms and main- 

 tains the peat mosses and quagmires in the moun- 

 tains which feed the streams at their feet. Mosses in 

 general are almost as much indebted for moisture to 

 the absorbing nature of their leaves as to their roots ; 

 but the loose, large celled, and perforated leaves of the 

 Sphagnum suck up water like a sponge ; even during the 

 heat of summer, a quantity of water may be squeezed 

 out of a handful of them. In fact the plant is a perfect 

 hydraulic machine, for a small" stem of it put into a 

 glass of water with its drooping terminal branch 

 hanging over the edge, acts like a syphon, and soon 

 empties the glass, pouring the water out through its 

 bending top. Though the peat from Sphagnum is 

 often too spongy for fuel at present, yet that little 

 moss now growing on our mountains will yield ani- 

 line, magenta, paraffin, and other illuminating gases to 

 remote generations, although not in such quantities as 

 the richer vegetation of the coal measures, the products 

 of a warmer period. 



Like all cryptogams the mosses are exceedingly 

 variable and difficult to distinguish. Not only does the 

 same species show great differences in size, but even 

 in other respects the characters vary on account of 

 climate, soil, and exposure. 



