so HISTORY OF BRITISH FERNS. 



Polypodium alpestre, Sprengel. 

 The A Ipine Polypody. (Plate XXI.) 



This Fern has so remarkably the aspect of the common 

 Lady Fern {Athyrium Filix-foemina), that although 

 common on the Scottish mountains, it has been till very 

 recently overlooked, the plants having been supposed to 

 belong to that species. It would appear to be plentiful on 

 the higher parts of the mountainous districts of the coun- 

 ties of Perth, Forfar, and Aberdeen, accompanying the 

 Lady Fern in its lo\yer range, but ascending to a consider- 

 ably higher elevation than that plant. The fronds appear 

 in May, and perish early in autumn. 



The plants of this Fern have a short decumbent caudex, 

 producing fronds in tufts from the crown. They are from 

 six inches to three feet or more in height, broadly lance- 

 shaped, and attached by comparatively short stipes, clothed 

 with broadish-pointcd membranous scales. They are 

 bipinnate, or sometimes subtripinnate. Tlie lower pinnae 

 are gradually shorter, so that the outline is truly lanceo- 

 late. The pinnae are linear-lanceolate, taper-pointed, 

 spreading at an obtuse angle with the rachis. The pin- 

 nules have a slightly wavy midvcin, from which alter- 



