142 



ABOUT MOSSES AND LICHENS. [CHAP. 



Mosses have no stomata on their leaves or stem 

 though sometimes they occur upon the capsule but 

 it is evident that they absorb gases like other plants. 

 This they probably effect through the walls of the 

 cells composing their substance. 



FIG. 103. 



FIG. 102. 



Mosses are to be found everywhere. "The hard- 

 beaten sides of footpaths, the loose crumbling matter 

 at the base of rocks, the sand by the seashore, the 

 rich moist banks of ditches, the grassy meadow, the 

 naked clay, the deep recesses of woods, the peaty soil 

 of heaths and moors, the damp margins of pools or 

 swamps, and wet boggy ground, have their own appro- 

 priate- species ; not to mention the variety of mosses 

 which are truly aquatic, whether in rapid streams or 

 quiet waters. The mud-capped walls which are so fre- 

 quent in oolitic districts, produce always a multitude 

 of species, some of them of rare occurrence elsewhere, 

 while the little mounds made by ants are sometimes 

 extremely productive. The Phasca seems to luxuri- 



