Mosses and Lichens 



with the adjacent ends of the bundle next to it. On the inner 

 face of each tooth is a growth of cells extending inward as a thin 

 blade; the tip of each tooth is connected with a thin, papery 

 membrane which covers the opening of the spore-case. From 

 the under surface of this membrane, processes like little curtains 



Spore-case 

 with lid. 



Spore-case with 

 lid removed to show 

 epiphrasm. 



Polytrichum commune. 



Fontinalis antipyretics. Sum- 

 mit of spore-case with inner 

 teeth forming a cone; outer 

 teeth curled in. 



Three teeth showing bundles 

 of fibres. 



hang down and in the young stages of the spore-case reach the 

 basal membranes, so that the case is completely closed. Later, 

 when the spores are mature, the "curtains" shrink away from the 

 basal membranes and leave little 

 holes between the teeth for the exit 

 of the spores. 



In the species of Catharinea the epi- 

 phragm is not attached to the apices 

 of the teeth, but hangs from them 

 by processes which at first exactly 

 line the inner surfaces of the upper 

 parts of the teeth. As the spores 

 within the spore-case mature they 

 exert a pressure upon the under 

 surface of the epiphragm which 

 causes it to rise and at the same 

 time to peel upward the lining of 

 each tooth. As the linings of the 

 teeth are torn away, they curve 

 upward and inward until they lie 

 against the under surface of the 

 epiphragm, which then appears to 

 rest upon the tips of the teeth. ^^SKSSSSJ" 

 When in this position, the tiny Potytrichum commw*. 



