POLYPODIACEAE 13 
sori oblong, borne about midway between the midrib and the margin of the blade, nearly 
or quite straight. [A. parvulum Mart. & Gal., not Hook. ] 
Often on limestone, Virginia to Missouri, Florida, Texas, New Mexico and Mexico. 
5. Asplenium platyneùron ( L.) Oakes. Rootstock short. Leaves evergreen, tufted ; 
petioles purplish brown and shining, 2.5-10 cm. long; blades linear, 2-4 cm. long, firm, 
pinnate, the rachis chestnut-brown ; leaflets 20-40 pairs, lanceolate, subfalcate, alternate 
or partly so, sessile, crenate, serrate or incised, auricled on the upper side at the base and 
occasionally also on the lower ; lower leaflets gradually smaller and oblong, or triangular : 
sori 8-12 on each side of the midrib, crowded at maturity. [A. ebeneum Ait. ] 
On rocks and shaded slopes, Maine and Ontario to Colorado, south to Florida and Texas. 
6. Asplenium Trichómanes L. Rootstock short, nearly erect, with blackish scales. 
Leaves densely tufted, numerous ; petioles 2.5-12 cm. long, purplish brown and shining ; 
blades linear in outline, 7-20 cm. long, rather rigid, pinnate, evergreen ; leaflets oval or 
roundish oblong, inequilateral, cuneate at the base, their margins slightly crenate ; sori 
3-6 on each side of the forking and evanescent midrib, short, narrowed at both ends. 
On rocks, preferring limestone, nearly throughout North America. Also in Europe and Asia. 
7. Asplenium dentátum L.  Petioles tufted, 5-15 cm. long, naked, blackish below. 
Fertile leaf-blades 5-7.5 cm. long, with 6-8 pairs of stalked oblong or rhombic leaflets, the 
lower side truncate with a curve, the outer edge irregularly crenate ; sterile leaves similar 
but with shorter petioles : rachis naked : sori copious, in parallel rows. 
In sandy soil, South Carolina to Florida. Also in the West Indies. 
8. Asplenium angustifòlium Michx. Rootstock stout. Fertile leaves usually taller 
than the sterile. Petioles in a crown, chaffless, or merely scaly at the base, 2-3 dm. long, 
brownish or greenish above ; leaf-blades lanceolate, 3-8 dm. long, pinnate ; leaflets linear- 
lanceolate or those of sterile leaves lanceolate, in 20-30 pairs, acuminate, entire or crenulate, 
obtuse or truncate at the base: sori 20-30 on each side of the midrib, linear, crowded. 
In moist or rich woods, Quebec to Wisconsin, Virginia, Georgia and Alabama. 
9. Asplenium fírmum Kunze. Petioles 10-20 cm. tall, naked, grayish. Leaf-blades 
15-30 cm. long; leaflets oblong-lanceolate, 12-20 pairs, blunt-pointed, minutely crenulate, 
the upper margin abruptly narrowed at the base, the lower obliquely truncate: sori short, 
not reaching either margin or midrib. : 
In eaverns, peninsular Florida. Also in the West Indies. 
10. Asplenium Rüta-murària L. Rootstock ascending. Leaves tufted; petioles 
naked, green, 5-7 cm. long; blades ovate or deltoid-ovate, 5-12 cm. long, glabrous, ever- 
reen, 2-3-pinnate, or pinnatifid above ; leaflets stalked, rhombic or obovate, mostly obtuse, 
entate or incised, cuneate at the base; veins flabellate: sori few, linear-oblong, confluent 
when mature and nearly covering the leaflet: indusia membranous and delicate. 
On limestone, Vermont to Michigan and Missouri, south to Connecticut, Alabama and Arkansas. 
Also in Europe, Asia and northern Africa. 
11. Asplenium montànum Willd. Rootstock chaffy at the summit. Leaves tufted ; 
petioles naked, slender, blackish at the base, 5-7 cm. long ; blades 5-20 cm. long, ovate- 
lanceolate in outline, acuminate, rather firm, 1-2-pinnate ; lower leaflets longest, pinnate or 
pinnatifid, the lobes or segments ovate or oblong ; upper less divided, merely toothed or in- 
cised ; veins obscure : sori linear-oblong, short, the lower ones sometimes double. 
On rocks, Connecticut to Ohio and Arkansas, and in the mountains to Georgia and Alabama. 
12. Asplenium Bradleyi D. C. Eaton. Rootstock chaffy with brown scales. Leaves 
tufted ; petioles slender, 5-7 cm. long, chestnut-brown ; blades oblong-lanceolate or oblong, 
acuminate, not narrowed at the base, with 8-12 pairs of short-stalked or sessile oblong- 
ovate leaflets ; the lower again pinnatifid or pinnate, with oblong obtuse lobes or pinnules, 
which are toothed at the apex, the upper pinnatifid with dentate or nearly entire lobes: 
rachis brown : sori near the midrib, covered with the narrow indusia until mature. 
On rocks, often preferring limestone, New York to Illinois and Missouri, south to middle Georgia, 
Alabama and Arkansas. 
13. Asplenium cicutarium Sw. Petioles greenish, tufted, 10-20 cm. long, naked. 
Leaf-blades 15-38 cm. long, with 10-15 pairs of horizontal leaflets, the lower ones 5-7.5 
em. long, parted into linear or oblong segments which are once or twice cleft at the apex : 
rachis compressed and often winged : sori mainly in 2 rows. 
In swamps, Sumter County, Florida. Also in tropical America. 
14. Asplenium myriophyllum Mett. Petioles tufted, 5-15 cm. long. Leaf-blades 
lanceolate, 8-30 cm. long, 2-3-pinnatifid ; segments entire, or 2-3-lobed, each bearing a 
single vein and a sorus. 
On rocks in sink-holes, peninsular Fiorida. Also in tropical America.—A form with narrowly 
linear leaf-blades 1.8-2.5 em. wide, and 7-8-lobed widely ascending leaflets, is known as A. myriophyllum 
Biscayneànum D. C. Eaton. 
