14 FERNS OP THE LAKE COUNTRY 



lasting till new ones are produced), growing luxuriantly 

 on tree trunks, moist rocks and walls, and mossy banks, 

 easily distinguished by its large round patches of orange 

 or tawny-brown spore-cases, no other of our native ferns 

 having its fructification at all similar in appearance. 



The rhizome of the Common Polypody is often as 

 thick as a man's little finger, covered with light brown 

 chaff-like scales, tapering to a point, sometimes droop- 

 ing so as to leave the upper surface smooth and greenish. 

 From this upper surface spring *the fronds, and from 

 the lower side chiefly the densely-matted fibrous roots 

 by which it clings for support. The stipes (or stalk) is 

 naked, sometimes nearly as long as the leafy portion, the 

 whole frond measuring from two to eighteen inches or 

 more. The general outline is lance-shaped, very deeply 

 pinnatifid, the lobes or segments oblong, generally 

 round but sometimes bluntly pointed at the end, and 

 occasionally notched along the margin. Each lobe has 

 a slightly wavy mid-vein, or rib, branching alternately, 

 each branch having four or five alternate branchlets, 

 the lowest of which on the side next the point of the 

 frond (rarely any other) produces a sorus at its club- 

 shaped head. The fructification is usually confined to 

 the upper part, and is generally ripe by the end of Sep- 

 tember. 



The Common Polypody differs essentially from all 

 the other British species associated with it, in having 

 its fronds articulated with the rhizome, that is at- 

 tached in such a manner that they fall off at the ap- 

 proach of decay. Its texture, too, is stouter and firmer 

 than that of other native species. The rhizome is per- 



