30 FERNS OF GREAT BRITAIN, 



as a British plant was fully recognised by botanists, and 

 it was proved to be the fern known by Continental 

 writers as Aspidium alpestre, or Jspidium Bhdticum. It 

 is so like the Lady Fern {Athyrium Mlix-fcBmind) in its 

 outline and general appearance, that it has doubtless 

 often been overlooked, and believed to be an alpine 

 variety of that plant ; for it has since been found to be 

 a not unfrequent fern on mountains in the north of 

 this kingdom. Some writers consider that this fern has 

 at an early period of its growth an indusium over its 

 circular clusters, and this may have induced the Conti- 

 nental botanists to class it with Aspidium. Mr. Newman 

 constitutes it a new genus, and calls it Pseudathyrium ; 

 while a very elegant form of the fern, termed by him 

 F fiexile, may eventually prove to be a distinct species, 

 or it may be but a variety of this plant. 



This alpine Polypody is a very graceful fern, the 

 fronds growing in circular clumps from the crown of a 

 creeping rhizome, and being a foot or a foot and a half 

 high. These fronds are lanceolate, twice-pinnate, nar- 

 rowed to the base, as much so as at the upper part of 

 the frond, and the leafy portion extends almost to the 

 base of the scaly stalk. The pinnae are lanceolate and 

 tapering ; the pinnules lanceolate, acute, and deeply pin- 

 natifid, with serrated segments. The clusters of fructi- 

 fication are small and circular, and are generally placed 

 on the depressed spots between the lobes of the pinnule, 

 and thus form two distinct lines on each side of the 

 midrib, and parallel to it ; but sometimes they are more 

 numerous, and in maturity form one mass. 



