PTERIDOPHYTA. II 



Leaves once pinnate. 



Pinnae 7 mm. -8 cm. long, mostly blunt. 

 Rachis chestnut-brown or blackish. 



Pinnae auricled at the upper side of the base. 



Pinnae opposite, oblong ; rachis dark brown or black. 



3. A. parvulum. 

 Pinnae partly alternate, lanceolate ; rachis chestnut-brown. 



4. A. platyneuron. 

 Pinnae not auricled, partly alternate, partly opposite. 



5. A* Trichomanes. 

 Rachis green ; pinnas not auricled. 6. A. vtride. 



Pinnae 5-12 cm. long, acute or acuminate. 7. A. angustifolium. 



Leaves 2-3-pinnatifid. 



Stipes green ; leaves ovate-deltoid ; pinnules fan-shaped, veins flabellate. 



8. A. Ruta-muraria. 

 Stipes dark at the base, green above. 



Leaves ovate-lanceolate, broadest near the base. 9. A. montanum. 



Leaves lanceolate, broadest above the middle. 10. A.fontanum. 



Stipes chestnut-brown throughout, as also the lower part of the rachis. 



ii. A. Brc^dleyi. 

 Sori usually more or less curved, sometimes horseshoe-shaped, often crossing to the 



outer or lower side of the veinlet ; large ferns. 



Leaves 2-pinnatifid ; segments blunt, scarcely crenate. 12. A. acrostichoides. 



Leaves 2-pinnate ; pinnules acute, toothed or pinnatifid. 13. A. Filix-fcemina. 



1. Asplenium pinnatifidum Nutt. (I. F. f. 46.) Rootstock short, creeping, 

 chaffy. Stipes tufted, polished, blackish below, green above, 5-12 cm. long, 

 somewhat chaffy below, at least when young ; leaves broadly lanceolate in outline, 

 7-25 cm. long, firm, tapering upward to a long narrow tip, pinnatifid or the 

 lower parts pinnate ; lowest pinnae or occasionally several pairs sometimes taper- 

 ing to a point like that of the apex of the leaf ; lobes or pinnae rounded or the 

 lowest acuminate. On rocks, N. J. and Pa. to 111., south to Ga. and Ark. 



2. Asplenium ebenoides R. R. Scott. (I. F. f. 47.) Rootstock short, chaffy. 

 Stipes blackish tufted, 4-10 cm. long ; leaves lanceolate in outline, variable in 

 size and length, 8-25 cm. long, 2.5-5 cm - wide at the base, firm, tapering into 

 a very long narrow acuminate apex, pinnatifid, or commonly pinnate below, the 

 segments or pinnae lanceolate from a broad base, acute or acuminate, irregular in 

 length, the lower sometimes shorter than those just above ; sori several on each 

 segment, straight or slightly curved. On limestone, Conn, to Ind., south to Ala. 

 Local ; rare except in the last-named locality. 



3. Asplenium parvulum Mart. & Gal. (I. F. f. 48.) Rootstock short, chaffy 

 with black stiff scales. Stipes tufted, blackish and shining, 2.5-5 cm - l n g> leaves 

 rather firm, linear-oblong or linear-oblanceolate, 7-25 cm. long, 10-25 mm. wide, 

 once pinnate ; pinnae 4-12 mm. long, mostly opposite, oblong, obtuse, entire or 

 crenulate, auricled on the upper side and nearly sessile, the middle ones the long- 

 est, the lower gradually shorter and reflexed ; rachis dark brown or black ; sori 

 oblong, short, borne about midway between the midrib and the margin of the 

 pinnae, nearly or quite straight. On limestone, Va. to Fla., west to Mo., Tex., 

 and N. Mex. 



4. Asplenium platyneuron (L.) Oakes. (I. F. f. 49.) Rootstock short. 

 Stipes tufted, purplish -brown and shining, 2.5-10 cm. long ; leaves linear, 2-4 cm. 

 long, 1.2-3.5 cm. wide, firm, once pinnate, the rachis chestnut-brown ; pinnae 

 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 pinnae gradually smaller and oblong or triangular ; sori 8-12 on each side 

 of the midrib of the pinnae, becoming crowded at maturity. On rocks and banks, 

 preferring limestone soil, Me. and Ont. to Fla., west to Colo, and Tex. 



5. Asplenium Trichomanes L. (I. F. f. 50.) Rootstock short, nearly erect, 

 chaffy with blackish scales. Stipes densely tufted, numerous, 2.5-12 cm. long, 

 purplish -brown and shining ; leaves linear in outline, 7-20 cm. long, 12-20 mm. 

 wide, rather rigid, once pinnate, evergreen ; pinnae oval or roundish-oblong, in- 

 equilateral, partly opposite, partly alternate, or nearly all opposite, cuneate at 

 the base, the point of attachment to the dark brown rachis narrow, their margins 

 slightly crenate ; sori 3-6 on each side of the forking and evanescent midrib, short, 



