J 14 ENGLISH BOTANY. 



Ultimate veins running into the teeth. Sori distributed over the whole 

 of the frond, except a few pairs of pinnse towards the base, placed 

 on the first anterior branch of the vein running into the pinnules or 

 ultimate segments, or on several of the branches. Indusium very 

 minute, very finely lacerate, fugacious, often absent. Spores brown, 

 tuberculate, with numerous small blunt unequal tubercles. 



Yar. a. genuinum. 



Frond narrowly oblong, sometimes strapshaped-oblong, subparallel- 

 sided towards the middle ; pinnae acuminate ; pinnules strapshaped- 

 lanceolate or narrowly lanceolate, acute, separated, sometimes convex 

 from the margins being reflexed. 



Yar. /3. obtusatum. 



Fronds oblong-elliptical, with the sides more or less curved outwards 

 toward? the middle ; pinna) tapering gradually towards the apex, but 

 not acuminate ; pinnules oval-oblong or oblong, approximate, obtuse, 

 generally flat. 



Amongst stones and on rocks in alpine districts, frequent on high- 

 land mountains above 1800 to 4000 feet. It occurs on all the high 

 mountains of Perthshire ; on the Clova Mountains, Forfarshire ; and 

 Braemar Mountains, Aberdeen ; first found on mountains near Dalwhin- 

 nie and on Ben Alder, Inverness-shire, in 1841, by Mr. H. C. Watson. 

 It is recorded also from the counties of Banff, Argyle, and Sutherland. 



Yar. a, judging from the specimens I have, appears much more 

 frequent than var. (3, which grows side by side with var. a. I have 

 it from Lochnagar, Canlochan, Ben Hope, Ben Lawers, and the 

 Clova Mountains. 



Scotland. Perennial. Summer, Autumn. 



Fronds 1 to 3 feet high, extremely similar to those of A. Filix- 

 foemina, var. a simulating A. Filix-foemina var. ereetum, and var. (3 

 A. Filix-focmina genuinum, though the two forms of eu-alpestre are 

 less distinct than the above-named vars. of Filix-foemina : A. alpestre, 

 var. a having the frond attenuated towards the base, and var. /3 

 having the frond narrower than in Filix-foemina genuinum ; but even 

 in the barren state eu-alpestre may be distinguished by its stipes 

 being scarcely channelled above (there the rachis is), and with much 

 broader and paler scales, which are almost white and hyaline when 

 the frond first begins to expand. The most striking difference, how- 

 ever, lies in the round sori, which arises from their shape not beino- 



