Aspidium Filix-mas:—Root-stock short, stout, ascending or erect; stalks rarely over a foot long, very chaffy with large lanceolate-acuminate scales and smaller ones intermixed; fronds standing in a crown, one to three feet long, half-evergreen, firm-membranaceous, broadly oblong-lanceolate, slightly narrowed toward the base, pinnate or sub-bipinnate; pinnæ lanceolate-acuminate from a broad base, pinnatifid almost or rarely quite to the midrib; segments smooth and full-green above, slightly paler and bearing a few little chaffy scales beneath, normally oblong, obtuse or even truncate, slightly toothed, in another form ovate-lanceolate, acutish and pinnately incised; veins free, forked or pinnately branched into from two to five veinlets; sori rather large, nearer the midvein than the margin, commonly occurring only on the lower half or two-thirds of each segment; indusia convex when young, rather firm, smooth or minutely glandular, orbicular-reniform. _Aspidium Filix-mas_, Swartz, in Schraders Journal, ii., (1800) p. 38; Syn. Fil., p. 55.—Schkuhr, Krypt. Gew., p. 45, t. 44.—Willdenow, Sp. Pl., v., p. 259.—Link, Fil. Hort. Berol., p. 105.—Ruprecht, Distr. Krypt. Vasc, in Imp. Ross., p. 35.—Kunze, in Sill. Journ., July, 1848, p. 83.—Mettenius, Fil. Hort. Lips., p. 92; Aspidium, p. 55.—Eaton, in Gray’s Manual, ed. v., p. 666.—Milde, in Nov. Act. Acad. Nat. Cur., xxvi., ii., p. 507; Fil. Eur. et Atl., p. 118.—Miquel, Prolusio Fl. Jap., p. 117. _Polypodium Filix-mas_, Linnæus, Sp. Pl. p. 1551. _Polystichum Filix-mas_, Roth, “Fl. Germ., iii., p. 82.”—Koch, Syn. Fl. Germ, et Helv., ed. iii., p. 733. _Nephrodium Filix-mas_, Richard, “in Desvaux, Mém. Soc. Linn., vi., p. 60.”—Hooker, Brit. Ferns, t. 15; Sp. Fil., iv., p. 117.—Hooker & Baker, Syn. Fil., p. 272 (excl. vars. γ and δ). _Dryopteris Filix-mas_, Schott, Gen. Fil.—Newman, Hist. Brit. Ferns, ed. iii., p. 184. _Lastrea Filix-mas_, Presl, Tent. Pterid., p. 76.—Moore, Brit. Ferns, Nat. Pr., t. xiv, xv, xvi, xvii. Var. _incisum_, Mettenius:—Frond ample, two to three feet long, scantily chaffy on the rachis; segments rather distant, lanceolate, tapering to a sub-acute point, incised on the margins with serrated lobules; indusium rather delicate, in age shrivelling or falling off.—Aspidium, p. 55; Milde, Fil. Eur. et Atl., p. 120.—_Lastrea Filix-mas_, var. _incisa_, Moore, l.c.—_Nephrodium Filix-mas_, var. _affine_, Hooker & Baker. l.c.