DEFINITIONS OF TERMS. 



All ferns have roots which are more or less fibrous ; 

 being sometimes very fine, tough, and wiry, and some- 

 times thick, brittle, and fleshy. The finer fibrous roots 



may be illustrated by those of the Scaly Spleenwort ; 

 the thick, brittle, and fleshy ones by those figured in the 

 sketch, on this page, of the Moonwort (Botrychium 



