PERNS OP GREAT BRITAIN. 115 



This fern is not peculiar to Tunbridge "Wells, though 

 found on several moist rocks in that neighbourhood; 

 and having been first discovered there, the plant is 

 known by the trivial name Tunhridgense, not alone in 

 this kingdom, but on several parts of the Continent. 

 It is not a rare fern, as it groves amongst, moss in damp 

 and shady places, especially in mountainous or rocky 

 districts in several parts of this country, as in Tilgate 

 forest, Sussex; on Dartmoor, in Devonshire; in many 

 parts of Cornwall; in several localities of Cumberland, 

 Westmoreland, and Lancashire. It is also of frequent 

 occurrence in Wales and Ireland, and in the latter 

 country is sometimes very luxuriant. 



2. H. unildterale (Wilson's Eihny Fern or Scottish 

 Filmy Fern). — Fronds pinnate ; pinna curving back- 

 wards ; segments linear, entire or two-cleft. This is a 

 small film-like fern, growing on wet rocks in various parts 

 of England and Wales, and very abundant in the High- 

 lands of Scotland, as well as in many parts of Ireland. 

 Though it grows, like the Tunbridge Fern, in matted 

 fronds, and the two plants are often found on the same 

 rock, yet it is a very distinct species. The fronds are 

 much more rigid, of a brownish green tint, somewhat 

 drooping in attitude, and the pinnae turning back in a 

 direction contrary to that of the fructification. They 

 are about two or three inches long; their outline is 

 linear-lanceolate and pinnate. The rachis is somewhat 

 arched, and the pinnae are convex above, all turning one 

 way, so that the fronds are more or less one-sided. The 

 wedge-shaped pinnae are cut into slender, blunt, pinna- 

 tifid segments, having a serrated and slightly spinous 



