CH. XI] THE MOSSES 487 



The compacted peat from the lower levels of the bogs forms 

 a valuable fuel, much used in Ireland especially. The looser 

 moss of the upper layers, and especially of the raised bogs, 

 makes valuable litter in stables, is much used by florists in 

 packing plants, and is utilized, because of its antiseptic and 

 absorptive properties, as a dressing in surgery. The anti- 

 septic property of the bogs causes also the preservation of 

 animal bodies, and thus the remains of men and other 

 animals, which become buried in them, remain often long 

 intact. In this way, also, the bones of extinct animals, 

 like the Mastodon and Great Irish Elk, have been preserved 

 to our own time. 



ORDER. BRYALES: THE TRUE MOSSES. These are the 

 Mosses par excellence, distinctive of much drier places than 

 the Peat Mosses. Their densely-crowded, small leafy 



fl.t 



(Fig. 346) f rise from creeping protonemata and 

 send down stout rhizoids, this arrangement enabling them 

 To advance over the ground much as do the Qrfl.sap.Sj in snliH 

 jDhalanx.__ They occur in mat-like or tussock-like masses not 

 only on the ground, but on fallen tree trunks, and even on 

 standing trees, where they become true epiphytes; and 

 they are also familiar on old fences, and roofs of old houses. 

 They are by no means confined to genial climates, but ex- 

 tend over open barren ground and moors, especially in arctic 

 and alpine places, where they follow close after the Lichens 

 in their occupancy of places too inhospitable for other life. 

 In such forms the typical intense green is 'often overlaid 

 by other bright colors. Thus they are the typical carpet 

 plants of the drier places of the earth as the Liverworts 

 are of the moister ; and our existent forms are presumably 

 the relics of an original green carpet which covered the 

 uplands of the world before any larger vegetation had 

 been evolved in those situations. They have no economic 

 uses. 



