PEENS OP GREAT BRITAIN". 25 



througlioiit tlie summer and autumn. It varies in height 

 from six inches to about a foot, the stalk being gene- 

 rally about twice as long as the leafy part, and slightly 

 scaly at the base. Its roots are black, wiry, hair-like 

 fibres. The frond is very distinct in its outline, being 

 triangular, and tapering at the upper part into a long 

 point. The lower part is pinnate, the pinnae being 

 narrow, cut nearly to the midrib, and very acute at the 

 point. They are usually in pairs, the lowest pair being 

 at some distance from the others, and turning backwards 

 towards the ground. They are united to the stem by 

 their midrib only ; but the other pinnae, which aU point 

 forwards, are united to the stem by their whole width, 

 and axe also connected with each other in a pinnatifid 

 manner. This turning backwards of the lower pinnae 

 gives so peculiar a character to this fern, that those who 

 have once seen it rarely find any difficulty in recognising 

 any further specimens which they may meet with. 



The lobes of the pinnae have each a slender vein run- 

 ning up the middle, from which, lateral veins, chiefly 

 unbranched, issue alternately, and extend to the margin, 

 each bearing a cluster of capsules at its extremity, 

 so that the fructification is nearly marginal. The 

 clusters are circular, and of a brownish hue. The 

 young fronds unfold their coils very early, and these 

 often droop backwards before fuUy expanding. It is 

 a very dehcate plant, perishing when placed in culture 

 where it is not protected ^rom the sun, and dying away 

 with the earhest frosts. Many writers dispute its claim 

 to be one of the Polypodies ; and it has been by various 

 botanists united with the genus Polystichum, or that 



