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 



__ ___ 6 T V 6 

 <J4.tu.'r& TlTYl 



..Of Spo-pE'CO.S 



Spore- sac, 



f.Spon--cas wall. 



oot. 



pedicel. 



eaves. 



Sphagnum acutifolium. Ehrh. Vertical section from a young sporogoniurn. 



(See page 49). 



Funaria hygrometrica. 

 Annulus. 



Fissidens adiantoides. 

 Old spore-case. 



53 



Tetraplodon mnioides, 

 Tip of spore-case. 



