Leafy Mosses 



TEETH OR PERISTOME 



When the lid falls, as a rule, one or two rows of teeth are 

 discovered. They are the remains of the cell-walls lying just 

 within the layer which separated as a lid. (See diagrams on 

 page 52.) 



If the outer walls of this layer of cells become thickened and 

 split from the summit downward, but one row of teeth will be 

 formed; if the inner walls as well, become thickened, and only 



Groove 



pedicel. 

 tcal I eaves. 



Sphagnum acuttfolium. Ehrh. Vertical section from & young sporogonium, 

 (See page 49). 



Funaria hygrometrica. 



Annulus. 



Fissidens adianioides. 

 Old spore-case. 



5) 



Tetraplodon mnioidtt, 

 Tip of spore-case. 



