Polypodium.] XCIV. FILICES 559 



sori even when young. For the Table of Species, see the Generic 

 Table above, p. 554, n. 13. 



1. P. vulgare, Linn. (fig. 1281). Common P. — Eootstock thick, 

 woody, and creeping. Fronds about 6 inches to a foot high, of a firm 

 consistence, without any scales on their stalk, broadly oblong-lanceolate 

 or somewhat ovate in their general outline, simply pinnate or deeply 

 pinnatifid ; the linear-oblong segments adhering to the main stalk and 

 usually connected with each other by their broad bases. Sori rather 

 large, of a golden yellow, in two rows along the under side of the 

 upper segment. When bearing fruit these segments are usually entire 

 or nearly so, and obtuse ; when barren they are often slightly toothed ; 

 and monstrous states not unfrequently occur with the segments 

 variously lobed or branched. 



In sheltered places, on trunks of old trees, walls, moist rocks, and 

 shady banks, throughout Europe and temperate Asia, from the Mediter- 

 ranean to the Arctic regions, and in North America and Souttr Africa. 

 Common in Britain. Fr. summer and autumn. [P. cambricum, Willd. 

 is a Welsh form with pinnatifid segments.] 



2* P. Phegopteris, Linn. (fig. 1282). Beech Fern. — Eootstock creep- 

 ing. Fronds rather slender, 6 inches to a foot high or rather more, 

 including their long stalks, broadly ovate-lanceolate and acuminate in 

 their general outline, once pinnate ; the segments deeply pinnatifid, 

 narrow-lanceolate, gradually diminishing from the base to the end of 

 the frond, and all, except sometimes the lowest pair, adhering to the 

 main stem by their broad base. The midrib, principal veins, and 

 margins of the frond more or less hairy on the under side, by which 

 this species may be readily distinguished from the smaller specimens 

 of Aspidium Thelypteris, which it sometimes resembles. Sori rather 

 small, near the margins of the lobes. Phegopteris polypodioides, Fee. 



In moist situations, in hilly districts, in Europe and Western Asia, 

 from the Pyrenees and Alps to the Arctic regions, and in North America. 

 In Britain, in western and northern England, Scotland, and Ireland. 

 Fr. summer and autumn. 



3. P. alpestre, Hoppe. (fig. 1283). Alpine P. — Stock short, often 

 forming several crowns. Fronds tufted, 1 to 3 feet high, twice pinnate ; 

 the segments numerous, oblong or lanceolate, deeply pinnatifid, and 

 sharply toothed, the larger ones usually about half an inch long. Sori 

 circular, without any indusium whatever ; this character alone dis- 

 tinguishes this plant from the smaller states of Asplenium Filix-fcemina 

 and from some forms of Aspidium spinulosum, which it closely resembles 

 in all other respects. Athyrium alpestre, Milde. 



In the mountains of Europe and western Asia, from the Alps and the 

 Caucasus to the Arctic regions. In Britain, only in the Highlands of 

 Scotland. Fr. summer. [P. flexile, Moore, is a variety found in the 

 Forfarshire mountains, with very short stalks and segments.] 



4. P. Dryopteris, Linn. (fig. 1284). Oak Fern. — Eootstock creep- 

 ing, rather slender. Fronds slender but erect, on long stalks, broadly 

 triangular or rhomboidal in their general outline, the leafy part 4 to 6 

 inches long and at least as broad, twice pinnate, or rather, in the first 

 instance, ternate ; the lower pair of branches or pinnas on slender 

 stalks, each often as large and as much divided as the rest of the frond ; 

 the others much smaller and less divided, the terminal ones reduced to 



