A. acrostichoides (Acrostichum-like).* sti. 6in. to 8in. long, densely scaly below. fronds 1ft. to 2ft. long, 2in. to 6in. broad; pinnæ of the lower half barren, 2in. to 3in. long, ¼in. broad, spinoso-serrated throughout, auricled at the base above; the pinnæ of the upper half fertile, much smaller. sori occupying the whole under side. North America. SYN. Polystichum acrostichoides. Hardy.
A. a. grandiceps (large-crested).* A very handsome fern, having the apices of the fronds and pinnæ heavily crested; equally desirable for the hardy or temperate fernery. Of garden origin.
A. a. incisum (incised).* A variety with the pinnules deeply cut and acutely pointed.
A. aculeatum (sharp-pointed).* The Hard Shield Fern. sti. tufted, 6in. to 12in. long, more or less scaly. fronds 1ft. to 3ft. long, 6in. to 12in. broad, ovate-lanceolate; lower pinnæ close, lanceolate, 4in. to 6in. long, ½in. to ¾in. broad; pinnules ovate-rhomboidal, unequal sided, auricled on the upper base; teeth aristate. sori nearer the midrib than the edge. A variable and hardy species, common throughout the world. SYN. Polystichum aculeatum. A. a. proliferum is a proliferous Australian form. A. a. vestitum has the rachis densely clothed to the point, both with reddish-brown fibrillose and large lanceolate dark brown scales. See Fig. 166.
A. amabile (lovely). sti. scattered, 6in. to 12in. long, slightly scaly below. fronds 1ft. or more long, 6in. to 12in. broad, with a lanceolate terminal pinna, and three to six lateral ones on each side, which are 3in. to 6in. long, 1in. to 1½in. broad, the lowest sometimes divided at the base; segments sub-rhomboidal, with at least half the lower side cut away, the upper side and part of the lower lobed and sharply spinuloso-serrated. sori sub-marginal. Ceylon. Stove species. SYN. Polystichum amabile.
A. angulare (angular). The Soft Shield Fern. Botanically this is only a variety of A. aculeatum; but, to the cultivator, it is abundantly distinct. The fronds are not so tapered at the base, the pinnules are more equal in size, and the lower ones distinctly stalked, while the texture is much less rigid than in A. aculeatum, the caudex has a tendency to elongate. Almost cosmopolitan in its distribution. SYN. Polystichum angulare. There are an enormous number of varieties, many of which are not under cultivation. Amongst the best found in gardens are alatum, Bayliæ, concinnum, corymbiferum, cristatum, curtum, dissimile, grandiceps, imbricatum, Kitsoniæ, lineare, parvissimum, plumosum, polydactylon, proliferum, rotundatum, Wakeleyanum, Woollastoni.
FIG. 167. ASPIDIUM ANGULARE GRANDICEPS.
A. a. grandiceps (large-crested). This is a narrow fronded variety, having the apices of the fronds branched and crested, ultimately producing a broad tasselled head. A very handsome fern. See Fig. 167.
A. anomalum (anomalous). sti. tufted, 1ft. to 2ft. long, densely scaly below. fronds 2ft. to 3ft. long, 1ft. or more broad; lower pinnæ 6in. to 9in. long, 2in. to 3in. broad; pinnules lanceolate, cut down in the lower part into oblong segments; teeth blunt or slightly mucronate. sori placed near the sinuses of the pinnules. Ceylon. Stove species. SYN. Polystichum anomalum.
A. aristatum (awned).* rhiz. creeping. sti. scattered, 9in. to 18in. long, very scaly below. fronds 1ft. to 2ft. long, 9in. to 12in. broad, ovate-deltoid, tri- or quadripinnatifid; lower pinnæ largest, 4in. to 6in. long, 2in. to 3in. broad; lowest pinnules much the largest, lanceolate-deltoid; teeth copious aristate. sori small, principally in two rows near the midrib. Japan, Himalayas, New South Wales, &c. Greenhouse species. SYN. Polystichum aristatum.
A. a. coniifolium (Conium-leaved).* fronds more finely divided; segments copiously toothed, with lower lobes distinct.
A. a. variegatum (variegated).* A handsome variety, with a broad band of green running through the bases of the pinnules along the course of the rachis.
A. auriculatum (eared).* sti. tufted, 4in. to 6in. long, scaly below or throughout. fronds 12in. to 18in. long, 2in. to 4in. broad; pinnæ numerous, sub-sessile, usually close, 1in. to 2in. long, about ½in. broad, ovate-rhomboidal, falcate, acute, spinoso-serrated, the upper base auricled, the lower one truncate. sori in two rows. India, widely distributed. Stove species. SYNS. A. ocellatum, Polystichum auriculatum.
A. a. lentum (pliant). Pinnæ cut into oblong mucronate lobes about half-way down to the rachis, the auricle sometimes quite free.
A. a. marginatum (margined).* A variety with more coriaceous texture; upper edge of the pinnæ slightly lobed.
A. capense (Cape).* sti. scattered, 1ft. to 2ft. long, densely scaly below. fronds 1ft. to 3ft. long, 12in. to 18in. broad, sub-deltoid; lowest pinnæ the largest, 6in. to 9in. long, 3in. to 4in. broad; pinnules and segments lanceolate, the latter bluntly lobed. sori very large and copious. South America, New Zealand, Cape Colony, Natal, &c. Greenhouse species. SYNS. A. coriaceum, Polystichum capense.
A. confertum (compressed). Synonymous with A. meniscioides.
A. coriaceum (leathery). Synonymous with A. capense.
A. falcatum (hooked).* sti. tufted, 6in. to 12in. long, densely scaly below. fronds 1ft. to 2ft. long, 6in. to 9in. broad, simply pinnate; pinnæ numerous, the lower stalked, ovate-acuminate, falcate, 3in. to 5in. long, 1in. to 2in. broad; edge entire or slightly undulated, the upper side narrowed suddenly, sometimes auricled, the lower rounded or obliquely truncate at the base. sori small, copious, scattered. Japan, China, Himalayas, &c. SYN. Cyrtomium falcatum.
A. f. caryotideum (Caryota-like) has pinnæ sometimes larger, sharply toothed, slightly lobed, sometimes auricled on both sides. SYN. Cyrtomium caryotideum.
A. f. Fortunei (Fortune's).* This differs from the type in having pinnæ narrower and more opaque. All are most useful house ferns, and quite hardy in many parts of the country. SYN. Cyrtomium Fortunei.
A. falcinellum (finely-hooked).* sti. tufted, 4in. to 8in. long, densely scaly. fronds 9in. to 18in. long, 3in. to 6in. broad; central pinnæ 2in. to 3in. long, ¼in. broad; point acute; edge finely serrated; the upper side bluntly auricled, the lower obliquely truncate at the base. sori in two long rows. Madeira. Greenhouse species. SYN. Polystichum falcinellum.
A. flexum (bending). rhiz. stout, wide-creeping. sti. scattered, 1ft. long, scaly. fronds 2ft. to 3ft. long, 9in. to 12in. broad; lower pinnæ lanceolate-deltoid, 4in. to 6in. long, 2in. to 4in. broad; pinnules lanceolate-deltoid, cut down to the rachis below into oblong bluntly-lobed segments. sori large, in two rows, copious. Juan Fernandez. Stove species. SYN. Polystichum flexum.
A. fœniculaceum (Fennel-leaved).* rhiz. creeping. sti. scattered, 6in. to 12in. long, densely scaly below. fronds 1ft. to 2ft. long, and 9in. to 12in. broad, lanceolate-deltoid, four to five pinnatifid; lower pinnæ 6in. to 8in. long, 3in. to 4in. broad; ultimate divisions linear, awned, with a firm texture. sori solitary. Greenhouse species. Sikkim, 7,000ft. to 10,000ft. SYN. Polystichum fœniculaceum.
A. frondosum (leafy). sti. scattered, 1ft. to 2ft. long, densely scaly below. fronds 18in. to 24in. long, 1ft. or more broad, sub-deltoid; lower pinnæ much the largest, long stalked; pinnules lanceolate; segments very unequal sided, pinnatifid, with rounded mucronate lobes, obliquely truncate at the base below. sori large, copious. Madeira. Greenhouse species. SYN. Polystichum frondosum.
A. Hookeri (Hooker's). sti. 1ft. or more long, naked. fronds 2ft. to 3ft. long; pinnæ 6in. to 8in. long, 1in. broad, cut down to a broadly-winged rachis into nearly close, spreading, entire, linear-oblong lobes ⅛in. broad. sori nearer the edge than the midrib. Malay Archipelago. Stove species. SYNS. A. nephrodioides and Cyclodium Hookeri.
A. laserpitiifolium (Laserpitium-leaved).* sti. 4in. to 6in. long, stramineous, scaly at base. fronds 12in. to 18in. long, 6in. to 9in. broad, ovate-deltoid, tripinnate; lower pinnæ the largest, with pinnules on the lower side prolonged, lanceolate, imbricated with small, distinct, bluntly-lobed segments. sori in two rows, very copious. Japan. A very desirable greenhouse species. SYNS. Lastrea Standishii (of gardens) and Polystichum laserpitiifolium.
A. lepidocaulon (scaly-stemmed). sti. tufted, 6in. to 9in. long, densely clothed with large cordate scales. fronds 1ft. or more long, 4in. to 6in. broad, sometimes elongated and rooting at the point: pinnæ 2in. to 3in. long, ½in. to ¾in. broad, lanceolate-falcate, the two sides unequal, the upper one auricled at the base. sori principally in two rows, near the midrib. Japan. Greenhouse species. SYN. Polystichum lepidocaulon.
A. Lonchitis (spar-like).* The Holly Fern. sti. densely tufted, 1in. to 4in. long, scaly at base. fronds 1ft. to 2ft. long, 1in. to 3in. broad, pinnate throughout; pinnæ ½in. to 1½in. long, ¼in. to ½in. broad, ovate-rhomboidal, sub-falcate, the two sides unequal, point mucronate, edge spinuloso-serrated, the upper side sharply auricled at the base, the lower obliquely truncate. Britain, &c. A very widely-spread hardy species. SYN. Polystichum Lonchitis.
A. meniscioides (Meniscium-like). sti. 1ft. to 2ft. long, scaly below. fronds 2ft. to 3ft. long, 1ft. or more broad, pinnate; barren pinnæ sessile, 6in. to 9in. long, 1½in. to 2in. broad, oblong-acuminate, nearly entire; fertile pinnæ much smaller. sori in two close rows between the primary veins. West Indies, &c. Stove species. SYNS. A. confertum and Cyclodium meniscioides.
A. mohrioides (Mohria-like). sti. tufted, 2in. to 6in. long, more or less densely scaly. fronds 6in. to 12in. long, 2in. to 3in. broad, bipinnate; pinnæ numerous, frequently imbricated, lanceolate, cut down below into slightly toothed, oblong-rhomboidal pinnules. sori copious. Patagonia and the Cordilleras of Chili. Greenhouse species. SYN. Polystichum mohrioides.
A. mucronatum (mucronated).* sti. tufted, 2in. to 4in. long, densely scaly. fronds 12in. to 18in. long, 1½in. to 2in. broad, pinnate throughout; pinnæ very numerous, often imbricated, ¾in. to 1in. long, ¼in. to broad, sub-rhomboidal, unequal-sided, mucronate, sub-entire, distinctly auricled at the upper base. sori in a long row on each side the midrib. West Indies. Stove or greenhouse species. SYN. Polystichum mucronatum.
A. munitum (armed).* sti. tufted, 4in. to 9in. long, densely scaly. fronds 1ft. to 2ft. long, 4in. to 8in. broad; pinnæ close, 2in. to 4in. long, about ½in. broad, acuminate, finely spinulose and serrated throughout, the upper side auricled, and the lower obliquely truncate at the base. sori in two rows near the edge. California, &c. Hardy; very fine. SYN. Polystichum munitum.
A. nephrodioides (Nephrodium-like). Synonymous with A. Hookeri.
A. ocellatum (spotted). Synonymous with A. auriculatum.
A. pungens (stinging). rhiz. stout. sti. scattered, 1ft. long, scaly below only. fronds 2ft. to 3ft. long, 9in. to 12in. broad; lower pinnæ 4in. to 6in. long, 2in. to 3in. broad; pinnules ovate-rhomboidal, unequal-sided, often deeply pinnatifid. sori principally in two rows near the midrib. Cape Colony. Greenhouse species. SYN. Polystichum pungens.
A. repandum (wavy-leaved). sti. 1ft. to 2ft. long, naked. fronds 2ft. or more long, 12in. to 18in. broad, apex deeply pinnatifid, with linear-oblong, slightly sinuated lobes; lower pinnæ four to eight on each side, 6in. to 8in. long, 1¼in. to 1½in. broad, acuminate; edge bluntly sinuated, the lowest stalked and forked. sori in two distinct rows near the main vein. Philippines. Stove species.
A. rhizophyllum (frond-rooting). sti. tufted, 1in. to 2in. long, slender. fronds 2in. to 6in. long, ¾in. broad, with the long, narrow upper half of the frond lengthened out and rooting, the lower half cut down to a flattened fibrillose rachis into oblong-rhomboidal sub-entire lobes about ½in. broad, ¼in. deep. sori scattered. Jamaica, 1820. Stove or cool house species. SYN. Polystichum rhizophyllum.
A. semicordatum (half-cordate). sti. scattered, 6in. to 12in. long. fronds 2ft. to 3ft. long, 8in. to 12in. broad, simply pinnate; pinnæ spreading, 4in. to 6in. long, ½in. to ¾in. broad, nearly entire, acuminate, cordate or truncate at the base. sori in one to three rows on each side, the inner one close to the midrib. Tropical America, &c. SYN. Polystichum semicordatum.
A. trapezioides (Trapezium-like). Synonymous with A. viviparum.
A. triangulum (triangular).* sti. tufted, 2in. to 6in. long, base scaly. fronds 1ft. or more long, 1½in. to 2in. broad; pinnæ numerous, sessile, lower ones distant, central ones ¾in. to 1in. long, about ⅝in. broad, sub-deltoid, lower side obliquely truncate; apex mucronate, edge sub-entire or slightly lobed, with blunt or spinose teeth, one or both sides auricled at the base. sori principally in two rows near the edge. West Indies. Stove or greenhouse species. SYN. Polystichum triangulum.
A. trifoliatum (three-leaved). sti. tufted, 1ft. or more long, base only scaly. fronds 12in. to 18in. long, 6in. to 12in. broad, with a large ovate-acuminate terminal pinna, narrowed or forked at the base, and one or two lateral ones on each side, the lowest mostly forked. sori in rows near the main veins. Tropical America. Stove species.
A. t. heracleifolium (Heracleum-leaved). A form with pinnæ pinnatifid on both sides at the base.
A. tripteron (three-winged). sti. 6in. to 9in. long, densely scaly at base. fronds 12in. to 18in. long, with a large terminal and two small spreading lateral pinnæ at the base of it, the former 2½ in. to 3in. broad, with very numerous spreading pinnules on each side, 1½in. long, about ½in. broad, unequal sided, acute, deeply inciso-pinnatifid, the lower lobes again toothed; lateral pinnæ 3in. to 5in. long, 1½in. to 2in. broad. sori principally in two rows midway between midrib and edge. Japan. Greenhouse species. SYN. Polystichum tripteron.
A. varium (variable).* rhiz. sub-creeping. sti. 6in. to 12in. long, densely fibrillose below. fronds 12in. to 18in. long, 9in. to 12in. broad, lanceolate-deltoid; lower pinnæ much the largest, sub-deltoid, unequal sided, 4in. to 6in. long, 3in. to 4in. broad; pinnules lanceolate, imbricated, with oblong, blunt, slightly toothed segments. sori principally in two rows near the midrib. Japan. Greenhouse species. SYNS. Lastrea varia and Polystichum varium. It is frequently met with in gardens under the former name.
A. viviparum (bud-producing). sti. tufted, 4in. to 6in. long, scaly at the base. fronds 12in. to 18in. long, 4in. to 6in. broad; pinnæ numerous, nearly lanceolate, the central ones 2in. to 3in. long, about ½in. broad, mucronate, sometimes bud-bearing, the edge more or less deeply lobed, in the lower part sometimes quite down to the rachis, the upper side auricled. sori in two or four rows. West Indies. Stove or greenhouse species. SYNS. A. trapezioides and Polystichum viviparum.
ASPLENIUM (from a, not, and splen, spleen; referring to the medicinal properties formerly attributed to the genus). Spleenwort. ORD. Filices. Including Anisogonium, Athyrium, Ceterach, Cænopteris, Darea, Diplazium, Hemidictyum, Neottopteris. A very large and widely-spread genus, including species suitable for the stove, temperate, and hardy ferneries. Sori dorsal or submarginal, linear or oblong. Involucre similar in shape, straight or occasionally curved, single or double, plane or tumid, bursting along the outer edge. The tropical species should be grown in a compost of peat, loam, and sand; the hardy sorts in a mixture of fibrous peat and sand. Good drainage is at all times required. For general culture, see Ferns.
FIG. 163. ASPLENIUM ADIANTUM-NIGRUM, showing Rootstock and back of Fertile Fronds.
A. abscissum (clipped). sti. tufted, 4in. to 8in. long. fronds 6in. to 12in. long, 3in. to 4in. broad, sometimes proliferous at the apex, with twelve to twenty horizontal pinnæ on each side, which are 1½in. to 2in. long, about ½in. broad, bluntish; edge inciso-crenate, the upper one narrowed suddenly at the base, the lower one obliquely truncate. sori short, in two regular rows, falling short of both midrib and edge. Tropical America. Stove species. SYN. A. firmum.
A. acuminatum (taper-pointed).* sti. 6in. to 9in. long. fronds 1ft. to 2ft. long, 9in. to 12in. broad, with very numerous close-placed lanceolate-oblong pinnæ on both sides, which are 4in. to 6in. long, 1½in. to 2in. broad; pinnules numerous, unequal-sided, lanceolate, acuminate; edges sharply toothed, the lower base obliquely truncate. sori in two rows in the upper part, of the pinnules, often diplazioid. Sandwich Islands. Greenhouse species. SYN. A. polyphyllum.
A. Adiantum-nigrum (Black Spleenwort). sti. tufted, 6in. to 9in. long. fronds 6in. to 12in. long, 4in. to 6in. broad sub-deltoid; lower pinnæ deltoid, 2in. to 3in. long, 1½in. to 2in. broad; all the pinnæ pinnate. sori copious, at last often occupying the whole under surface of the segments. Great Britain. World-wide in its distribution. Hardy. A. solidum, from Cape Colony, is supposed to be a mere form of this species. There are several varieties the best of which are described below. See Fig. 168.
A. A.-n. acutum (acute). fronds 9in. to 15in. long, deltoid, tripinnate; ultimate segments linear, and very acute. Ireland. A copiously divided and very elegant variety. Habit more graceful than the type.
FIG. 169. ASPLENIUM ADIANTUM-NIGRUM GRANDICEPS.