14 PERNS or GEE AT BRITAIN. 



mould formed of the falling leaves of many winters, or 

 they wave unseen over the stones of quarries, or among 

 rocks; but their number has doubtless been greatly 

 lessened by the increase of agriculture during past 

 centuries. Not one British fern grows in water. 



The terms employed in the description of Ferns are 

 few. A linear leaf, or leaflet, is one of which the two 

 sides are parallel, like the leaf of the grass : the term 

 decurrent signifies that the leafy portion runs down the 

 side of the stalk, and gradually merges into it. The 

 margin is sometimes serrated or notched like the edge 

 of a saw ; a fertile frond is one bearing the fructifica- 

 tion ; a barren frond, one from which that fructification 

 is absent. In some ferns, as in the Northern Hard Fern, 

 the barren and fertile fronds are differently formed. 



TABLE OF THE ORDERS AND GENERA OF THE 

 BRITISH FERNS, AND FERN-LIKE PLANTS. 



Order I. FILICES.— TRUE FERNS. 



This Order consists of flowerless leafy plants, their 

 leaves or fronds, with some few exceptions, gradually 

 unfolding in a scroll-like manner, and bearing their 

 seeds or spores in capsules on the backs or margins of 

 the fronds. These capsules are either one-celled and 

 stalked, with an elastic ring; or are without stalk or 

 ring. 



