1042 



THE FERN FAMILY. 



and northward up western France to the Channel Islands, the only 

 station within our Flora. It reappears in the southern hemisphere. 

 Fr. spring and summer. 



VII. SHIELDPERN. ASPIDIUM. 



Fronds (in the British species) once, twice, or thrice pinnate, with a 

 stiff erect stalk, usually bearing, at least at the base, numerous brown 

 scarious scales. Sori circular as in Polypody, but covered when young 

 by a membrane or indusium, attached by the centre or by a point near 

 one side, so that, when raised all round by the growth of the spore- 

 cases, it becomes either peltate or kidney-shaped. 



A very large genus, ranging over every part of the globe, only dis- 

 tinguished from Polypody by the indusium. In modern British Fern- 

 books it is usually divided into two, Lastrea and Polystiehum, accord- 

 ing to whether the attachment of the indusium is central or towards 

 the margin, a minute character, unconnected with habit, often difficult 

 to appreciate, and sometimes inconstant. The Table of Species will be 

 found under the Generic Table above, p. 1033, n. 13. 



1. Holly Shieldfern. Aspidium Lonchitis, Sw. 



(Fig. 1267.) 



(Polypodium, Eng. Bot. t. 797, Polystic7ium, Bab. Man. Holly Fern.) 



Stock short and thick. Fronds tufted, 

 usually 6 inches to a foot high or rather 

 more, stiff, linear-lanceolate in their 

 general outline, simply pinnate, leafy 

 from the base, the common stalk very 

 scaly below. Segments mostly broadly 

 lanceolate or almost ovate, curved, prick- 

 ly-toothed, enlarged at the base on the 

 inner or upper side into a toothed angle 

 or lobe, all nearly sessile, but attached 

 by the midrib only, stiff, glabrous above, 

 with a few scaly hairs underneath ; the 

 central ones about an inch long ; the 

 lower ones smaller and broader, often 

 ovate. Sori circular, rather large, with 

 a peltate indusium in the centre, which 

 is however not very conspicuous. 



In clefts of rocks, in all the great 

 mountain regions of Europe and central 



