84 MOSSES AND LIVERWORTS 



stalk will be tipped with a small brown head, 

 indicating that the capsule has arrived at maturity, 

 and on placing one of these, in a moist state, 

 under the microscope, the slight swelling at the 

 base, alluded to in a previous page (p. 52), will at 

 once become apparent, while the capsule mouth 

 is closed by the lid (operculum), thus precluding 

 the escape of the ripe spores inside (fig. 11). 



It will not be long now before the ring of cells 

 (annulus) just under the lid, which has also been 

 described (p. 61), comes into play (fig. 12), and, 

 rolling back, will lift the lid from the capsule 

 mouth, and so render it possible for the spores to 

 make their way out (fig. 13). The lid (operculum) 

 itself, when thus freed, forms a pretty object 

 under the microscope (fig. 14), and its fall, of 

 course, brings to view the fringe of teeth 

 (peristome), which guards the entrance to the 

 interior of the capsule. These particular teeth 

 are especially attractive, and will well repay a 

 closer acquaintance. Let us see what they look 

 like under different conditions. 



And first we will examine a dry capsule (fig. 15) 

 with a glass. Notice, in passing, its curiously 

 furrowed walls, so unlike their appearance when 

 the capsule has been moistened (fig. 11). The 

 teeth of the peristome, it will be seen, are closed 

 over the capsule mouth, this being a case in 

 which they only open under the influence of 

 moisture. It will be well, moreover, to get a 



