16 POLYPODIACEAE 



toid-lanceolate, or broadly so, 5-20 cm. long, acuminate, 1-2-pinnate, firm, evergreen; 



lower leaflets deltoid, pinnate or pinnatifid, the lobes or segments ovate or oblong; 



upper less divided, merely toothed or incised; veins obscure: sori short. 



On rocks, Connecticut to Ohio and Arkansas, and in the mountains to Georgia and 

 Alabama. 



13. Asplenium Bradleyi D. C. Eaton. Eootstock short, with narrow brown 

 scales. Leaves tufted; petioles stoutish, 5-7 cm. long, rich chestnut-brown; blades 

 oblong-lanceolate or oblong, acuminate, scarcely narrowed at the base, with 8-12 pairs 

 of short-stalked or sessile oblong to deltoid-ovate leaflets; lower leaflets often deltoid, 

 pinnatifid or pinnate, with oblong obtuse lobes, these toothed at the apex; rachis brown 

 or greenish above: sori near the midrib: indusium narrow. 



On rocks. New York to Missouri, south to middle Georgia, Alabama and Arkansas. 



14. Asplenium erosum L. Eootstock small, erect. Leaves numerous, tufted, 



2-5.5 dm. long, the old petioles long persistent, splitting, fibrous; petioles as long as 



the blades or shorter, brown to grayish-green, slender, naked; blades 1.5-3.5 dm. 



long, oblong-lanceolate to deltoid-ovate, acuminate, 2-pinnatifid; leaflets spreading, 



spaced, stalked, more or less falcate, long ciineate, commonly linear-lanceolate with 



a single ellii^tical to obovate basal segment above, very obliquely excised below, 



tapering to a long-caudate apex, the margins obliquely crenate to inciso-pinnatifid, or 



in simpler forms the leaflets oblong-elliptic, auriculate, subentire: sori numerous, 



linear-oblong, medial, very oblique. [A. auritum Sw.] 



Cedar hammock, Sumter County, Florida. Tliroughout tropical America, usually on 

 trees. Exceedingly variable, some of the forms nearly bipinnate. 



15. Asplenium Biscayneanum (D. C. Eaton) A. A. Eaton. Eootstock short, 

 erect, with narrow brown scales. Leaves numerous, clustered; petioles 4-15 cm. lo. 

 dull greenish brown above, darker below, naked with age; blades narrowly oblaneeo- 

 late to linear-oblong, 1-2.5 dm. long, very deeply bipinuatifid; leaflets 10-20 pairs, 

 ascending, 1-2 cm. long, oblong to rhombic-oblong or obovate; segments 5-7, the 

 basal ones free, cuneate-obovate, crenately lobed, the others narrower, shorter and 

 simpler: sori large, 2-4 in the larger segments. 



Moist limestone bluffs and sinks, Brickell hammock, Miami, Florida. 



16. Asplenium verecundum Chapm : Eootstock short, erect. Leaves numerous, 

 closely cespitose, 1-4 dm. long, the old bases often persistent; petioles mostly short 

 (rarely 10 cm. 'ong), slender, dull purplish-brown; blades linear-oblanceolate, attenu- 

 ate, 8-25 cm. long, 2.5-6 cm. broad, 2-3-pinnate, commonly tapering toward the 

 base; leaflets numerous, delicate, mostly oblong, pinnate or in large leaves bipinnate 

 at the base ; segments oblong-spatulate, more or less inequilateral, each with a single 

 short sorus on the included simple vein : indusium delicate. 



Crevices of shaded calcareous rocks, peninsular Florida. Also in Cuba. 



17. Asplenium criatatum Lam. Eootstock erect, fibrous. Leaves several or 

 many, cespitose, 2-7 dm. long; petioles short or as long as the blades, greenish to 

 brown, greenish margined; blades 3-pinnatifid or 3-pinnate, 1.5-4.5 dm. long, oblong 

 to ovate-lanceolate, attenuate above, at the base truncate or abruptly narrowed, or 

 frequently gradually reduced with many pairs of smaller leaflets; leaflets spreading, 

 numerous, close or apart, sessile, the larger ones oblong-lanceolate, 5-10 cm. long, 

 pinnate or 2-pinnate, the basal divisions often flabellately divided and overlying the 

 rachis; final segments linear-oblong to elliptical, acutish, with simple veins: sori 

 copious, solitary: indusia pale, thin, ample. [A. cicutarium Sw.] 



Moist rocky woods, Sumter County, Florida. General in tropical America. 



18. Asplenium Curtissil Underw. Eootstock short, stoutish, erect, with a few 

 acuminate brownish scales. Leaves numerous, fasciculate, 2.5-5 dm. long; petioles 

 8-17 cm. long, grayish brown, stoutish; blades lanceolate to oblong-lanceolate, 1-3.5 

 dm. long, 5-10 cm. broad, bipinnate or tripinnatifid, scarcely narrowed at the base; 

 leaflets ascending, oblong-lanceolate from a broader base, with about 6-9 pairs of 

 close very oblique broad narrowly cuneate segments, the larger of these usually 2-5- 

 cleft or deeply pinnatifid, the divisions mostly acute, decurrent: sori short, tumid. 



Among cavernous limestone rocks, in hammocks, Hernando and Citrus counties, Florida. 



18. ATHYRIUM Roth. 

 Medium-sized or large ferns, with greenish succulent petioles and herbaceous 

 1-3-pinnate or pinnatifid blades; veins free; scales of the rootstock delicate, of thin- 

 walled cells. Sori usually curved; oblong to linear-oblong, or crossing the vein and 



