riLiCES. 635 



Asia^ extending northward to Holland. In Britain, common in many parts 

 of ilngland and Ireland, but rare in Scotland. Fr. summer and autumn. 



XI. BIiECHNUM. BLECHNUM. 



Sori linear, one on each side of the midrib of eactt segment and parallel to 

 it. Indusium attached along the outer edge of the sorus, opening outwards 

 from the inner side. 



A small genus, spread over many parts of the world, but chiefly tropical. 



1. Hard Blechnum. Blechnum Spicant, Both. 

 {B. horeale, Eng. Bot. t. 1159.) 



Eronds simply pinnate, tufted, of two kinds, the outer barren ones spread- 

 ing, usually 6 mches to near a foot long; the segments lanceolate, curved, 

 entire, attached by their broad base ; those in the centre of the frond 1 to 

 I5 inches long, gradually decreasing towards each end. Eruiting fronds in 

 the centre of the tuft erect, 1 to li feet high; the segments of the same 

 length as ia tlie barren ones, but all narrow-linear; the under .side entirely 

 occupied by the 2 linear sori. 



In woods, and rather moist stony places and heaths, generally distributed 

 over Europe, extending from the Mediterranean far into Scandinavia, and 

 occurs ui several parts of Asia and Africa without the tropics. Common in 

 Britain. Fr. summer, rather late, and autvmn. 



XII. FTERXS. PTEEIS. 



Eronds usually stiff, often large, lobed or puinately divided. Veins of 

 the segments branching from a midrib. Sori linear, close along the margin 

 of the fi'ond, wdth an indusium attached along its outer edge to the margin 

 of the frond, and opening on the inner side. • 



A large genus, widely distributed over the globe, and if not very natural, 

 at any rate easily recognized. 



1. Brake Pteris. Pteris aquilina, Linn. 

 (Eng. Bot. t. 1679. BraTces or BracTcen.) 



A tall, erect, stiff Fern, with a thick, hard, creeping rootstock. Fronds 

 1 to 2 feet high in poor soils, 8 to 10 feet high when luxuriant, twice or 

 thrice pinnate ; the primai-y pinnas in pairs at some distance from each 

 other ; the lowest pair much larger, the others decreasing in size and succes- 

 sively developed, giving the whole frond, especially when young or small, 

 a broadly triangular outline. Secondary pinnas numerous, linear-lanceolate, 

 deeply pimiatifid or pinnate, always ending in an undivided, crenate, blunt 

 point. Segments ovate or oblong, obtuse and entire, attached by their 

 broad base, of a finn consistence, glabrous above, often hairy underneath. 

 Sori in continuous lines along the margins of the upper segments and sum- 

 mits of the secondary pinnas. 



In woods and thickets, on heaths and waste places, dry or moist, but not 

 swampy, in almost every part of the globe except the extreme north and 

 south. Yery abundant in Britain. Fr. auttimn. 



