CRYPTO'GAKIIA. 4[)1 



in this branch of physiology, ife examined 

 all that had been done before his time, de- 

 tected tile truth, raised mosses from seed, 

 and established their characters on the 

 principles we have already explained. 



The Linnsean genera of Mosses are 

 chiefly founded on the situation of the 

 capsule, whether lateral or terminal, with 

 some other circumstances. They are too 

 few, and not strictly natural. Hedwig 

 first brought into notice the structure of 

 the fringe, peristomium, which in most 

 mosses borders the orifice of the capsule. 

 This is either simple or double, and con- 

 sists either of separate teeth, or of a plaited 

 and jagged membrane. The external fringe 

 is mostly of the former kind, the inner, 

 when present, of the latter. The number 

 of teeth, remarkably constant in each ge- 

 nus and species, is either 4, 8, 16, 32 or 

 64. On these therefore Hedwig and his 

 followers have placed great dependance, 

 only perhaps going into too great refine- 

 ments relative to the internal fringe, which 

 is more difficult to examine, and less cer- 

 tain, thai* the outer. Their great crrof 



