THE OBLONG WOODSIA. 99 



head of Glen Isla, in Forfarshire, and on Ben Lawers, 

 and at Corrach Dh' Oufillach, between Glen Lochy and 

 Glen Dochart, in the county of Perth. But it is possibly 

 much more abundant than these rare " finds " would 

 seem to indicate. 



XXVIIL THE OBLONG WOODSIA. 



Woodsia ilvensis. 

 (Plate XV., Figs 2 and 3, page 77.) 



LENGTH OF FROND. Two to six inches. 



GENERAL DESCRIPTION. Roots fibrous, wiry. Root- 

 stock small, tufted. Fronds numerous, brittle, deciduous, 

 thick and woolly in texture, produced in clusters from 

 the crown ; stipes of varying lengths, generally rather 

 short, jointed, reddish, breaking off when the fronds 

 begin to decay a little distance above the crown ; leafy 

 parts hairy or woolly, oblong, lance-shaped, pinnate; 

 pinnae opposite or alternate, oblong, egg-shaped, short, 

 pinnatifid, and divided into small, blunt-pointed pinnules, 

 the incisions between which reach down almost to the 

 midstems of the pinnae. Fructification consisting of 

 spore -cases somewhat marginal upon the undersides of 

 the pinnules, and provided with indusia which lie as a 

 sort of scales under the sori, with a fringed margin, which 

 is spread over them. The thickly hair-covered under- 

 surfaces of the pinnules afford a sort of shelter for the 

 sporangia. 



HABITATS. Moist crevices of rocks in mountainous 

 districts at such altitudes as lie between twelve hundred 

 and three thousand feet above the sea-level. 



WHERE FOUND. InEngland, in the counties of Cum- 

 berland, Durham, Westmoreland, and York; in Durham, 



