627 
FIL1CES. (FERNS.) 
nate, free veins ; the indusium opening along the side towards the 
midrib or axis of venation. (Name from a privative, and <nr\rjv, 
the spleen , for supposed remedial properties.) 
§ 1. Asplenium proper ■ — Indusium straight, fixed by the rchole length. 
* Indusium flat or fialtish, membranaceous. (Fronds evergreen.) 
1. A. pinnatifidlllll, Nutt. Fronds (3'-6' long*diffusely 
spreading, lanceolate, pinnatijid, sometimes pinnately parted near the 
base, tapering above into a slender prolongation, with the apex some¬ 
times rooting; lobes roundish ovate, obtuse, cut-toothed or nearly en¬ 
tire ; the midrib evanescent by forking below the apex. —Cliffs on the 
Schuylkill and Wissahickon, near Philadelphia, JYutlaH, Miss Morris ; 
also southward: very rare. July.— Resembling the Walking Fern 
(Camptosorus), but the venation is that of Asplenium: fruit-dots 
irregular, numerous, even the slender prolongation fertile. 
2. A, Rllta-niliraria, L Fronds (2'-4' long) 2 -pinnate 
below , simply pinnate above, ovate in outline, the few divisions nar¬ 
rowly rhombic-wedge-shaped, toothed at the apex, without a midrib , the 
veins all rising from the base. — Limestone cliffs, rare. July. 
3. A. ill out a limn, Willd. Fronds (3'-5' high, bright green) 
ovate-lanceolate or triangular-oblong in outline, pinnate; the ovate 
pinnee pinnately 3-7 -parted (or the upper barely cleft) andevt-toothed; 
the veins forking from a midrib. — Cliffs, Alleghany Mountains in 
Penn. {Mr. Lea), and southward, rare. July. — Rachis green : stalk 
brownish. 
4. A. Tricll6llianes, L. Fronds (3'-8' long) in dense 
spreading tufts, linear in outline , pinnate ; pinnee numerous , roundish- 
oblong or oval (3 ,f -4" long), unequal-sided, obliquely wedge-truncate at 
the base, attached by a narrow point, the midrib evanescent; the 
thread-like stalk and rachis purple-brown and shining. (A. melano- 
caulon, Willd.) —Shaded cliffs, common. July. 
3. A* cbeneum, Ait. Fronds upright (8*-16' high), pinnate, 
lanceolate-linear in outline; pinnee (4' — 1' long) many, lanceolate, or 
the lower oblong, slightly scythe-shaped, finely serrate, sessile, the 
dilated base auricled on the upper or both sides; fruit-dots numerous 
on both sides of the elongated midrib ; stalk and rachis blackish-purple 
and shining —Rocky, open woods, common southward. Aug. 
* Indusium vaulted , thickish. {Fronds decaying in autumn, - 3° high.) 
6 A, angustifolilim, Michx. Fronds simply pinnate; pinn® 
linear-lanceolate, acute, minutely wavy-toothed (3'-4' long), on the 
fertile fronds usually more contracted and smaller; the linear-oblong 
turgid fruit-dots crowded. —Rich woods, from W. New England 
westward ; rather rare. Aug. 
7. A. thclypteroides, Michx. Fronds pinnate; pinrue deeply 
pinnatijid, linear-lanceolate (3'-o' long); the lobes oblong, o tu.e, 
