AspiDiuM. CLXIV. FILICES. C29 



♦ F^rond pinnate. 



1. A. ACROSTiciiolDEs. Willd. (Nephrodium. Michx.) 



Lcajlcts of the frond distinct, alternate, subsessile, lalcate-lanccolate, auri- 

 culate on the upper side at base, ciliatc-serrulate, only the upper ones fertile; 

 sort at length confluent; stipe chafly. — Common in rocky shades. Frond 15 — 18' 

 high, of a narrow-lanceolate outline. Stipe with loose, chafly scales, Leaflet.s 

 numerous, slightly curving upwards, 1 — 2' in length, the terminal ones, which 

 aU)ne are Iruitful, are contracted in size, the under side becoming overspread 

 Willi the sori. June — Aug. 



/?. incmim. Gray. (A. Schwenitzii, Beck.) Pinnae irregularly and incisely 

 dentate ; sort mostly distinct. — N. Y., N. J. and Penn. Pas.ses in.sensibly into a. 

 * * Frond pinnate with pinnalifid Icajleta. 



2. A. Thki-yptera. Willd. (A. Noveboracense. rjv.'.d.) Shidd-Fcrn. 



Linjlits of the frond linear-lanceolate, deeply pinnatifid, distinct, subses- 

 sile ; srL^'/nint.s oblong, obtuse or acute, subentire, ciliate ; sori marginal, small, 

 at length confluent; stipe smooth and naked. — Damp woods. Fronds pale 

 green, thin and delicate, about a foot long and J as wide, acuminate at apex. 

 Leaflets acuminate, becoming entire above, .sometimes cro.s.sing (decussating) at 

 base. Rachis pubescent. Stipe slender, channeled on the upper side. Sori 

 in 2 marginal rows on each segment, finally nearly covering their under sur- 

 face. July. 



p. Noveboracense. Rather paler and more delicate in texture ; leaflets more 

 narrow and remote. 



3. A. CRisTATUM. Willd. (Nephrodium. M.c.) Crested Shield-Fern. 

 Frond nearly bipinnate, lanceolate-ovate ; leaflets subcordate, oblong-pin- 



natifid, segments oblong, obtuse, ciliate-serrate ; stipe scdAy. — Moist woods and 

 meadows, N. Eng., Mid. States, rather rare. Frond 12 — 18' high, pale green, 

 remarkable for its broad, ovate-lanceolate outline. Segments of the leaflets some- 

 times almost distinct, broad and obtuse, with sharp teeth. Sori large, in double 

 rows, tawny when matuie, chiefly on the upper half of the frond. July. 



4. A. Lancastriense. Spreng. (A. cristatum. /?. l5/. edit.) Lancaster 

 Shield-Fern. — Stipe with a few large, oblong, torn scales, chiefly at base ; 



frond narrowly lanceolate; leaflets subopposite, remote, short-petiolulate, broad- 

 est at base, the lower triangular-ovate ; sori large, in a single row each side the 

 midvein of each dentate segment ; inditsinm fi^ed near one side. — Woods, 

 Meriden, N. H., BickardI to N. Y. and N. J. A beautiful fern, quite distinct 

 from the preceding, 24 — 30' high. Frond dark green, 15 — 18' by 5 — 8'. Leaf- 

 lets gradually narrowing from base to apex. Segments nearly distinct, more or 

 less distinctly serrate-dentate, each with 1 — 25 dark-brown sori (loAver leaflets 

 fruitless). July. 



5. A. GoLDiANUM. Hook. (A. Filix mas. Pursh.) Goldic's Fern. 

 Leaflets of the frond lanceolate, acuminate, deeply pinnatifid ; segments 



oblong, subacute, subfalcate, mucronate-serrate ; sori in 2 rows, each side of the 

 vein of each segment. A tall .species, 2 — 3f high, in rocky woods. Fronds 

 numerous, bright green, scaly upon the stipe and rachis, 5 — 10' wide. Leaflets 

 3 — 6' long, not widening at base, with elongated, narrow segments. July. 

 * * * Frond bipinnate. 



6. A. margixAle. Sw. (Nephrodium. Mr.) Marginal Shield-Fern. 

 Segments of the lc(/fl^ts oblong, obtuse, decurrent, crenate-sinuate, repand 



at base, lower ones almost pinnatifid ; sori marginal ; stipe chaffy. — A large, 

 handsome fern, in rocky MOods, common. Frond 12 — 18' high, ven,' smooth 

 (rachis a little chafly), its divisions nearly opposite. Segment'^ of the leaflets 

 aistinct, near an inch long, \ as wide, contracted at base, then decurrent, form- 

 ing a narrow margin along the rachis. Fruit in round dots, in regular rows 

 along the margins of the segments. Indusium large, orbicular, with a lateral 

 sinus. July. 



7. A. TENiE. Sw. (A. fragile. Willd. Cistopteris. Bcrnh.) Brittle 

 Shidd-Fcrn. — S-rgvients of thehafkts oblong, obtuse or acute, incisely ser- 

 rate, approaching to pinnatifid, its serratures subentire; racAw winged by the 



