42 POLYPODIACEAE (FERN FAMILY^ 



gradually shorter and deflexed ; lobes flat, oblong, basal ones often enlarged 

 and incised ; veins simple, or forked in the basal lobes ; fruit dots distinct, near 

 the margin ; indusium minute, the margin glanduliferous. {Dryopteris Gray.) 



— Rich woods; coramon. July. — Frond pale green, delicate and membranar 

 ceous, hairy beneath along the midribs and veins. 



4. A. frjl grans (L.) Sw. Fronds (1-3.5 dm. hlgh^ glandular and aromatic, 

 narrowly lanceolate, with linear-oblong pinnately-parted pinnae ; their crowded 

 divisions (2-4 mm. long) oblong, obtuse, toothed or almost entire, nearly 

 covered beneath with the very large thin imbricated indusia, which are orbicu- 

 lar with a narrow sinus, the margin sparingly glanduliferous and often ragged. 

 {Nephrodium Richards. ; Dryopteris Schott.) — Chiefly on limestone cliffs, N. B., 

 and n. N. E. to Minn., Alaska, and Greenl. (Caucasus, Asia.) 



5. A. marginkle (L.) Sw. Frond evergreen, smooth, thickish and almost 

 coriaceous, ovate-oblong in outline (3-7 dm. long) ; pinnae lanceolate, acumi- 

 nate, slightly broadest above the base ; pinnules oblong or oblong-scythe-shaped, 

 crowded, obtuse or pointed, entire or crenate ; frnit dots close to the margin. 

 {Nephrodium Michx. ; Dryopteris Gray.) — Rocky hillsides in rich woods ■. 

 common, especiallj' northw. Aug. Var. elegans J. Robinson is a form with 

 large fronds (2-2.5 dm. broad) which have the pinnules or most of them toothed 

 or lobed. 



6. A. Filix-m4s (L.) Sw. Frond lanceolate (3-11 dm. long) ; pinnae 

 linear-lanceolate, tapering from base to apex ; pinnules oblong, very obtuse, 

 serrate at the apex and obscurely so at the sides, the basal incisely lobed, dis- 

 tinct, the upper confluent ; fruit dots nearer the midvein than the margin. 

 usually confined to the lower half of each fertile pinnule. {Dryopteris Schott.) 



— Rocky woods, Nfd., N. S., n. Vt., L. Huron, L. Superior, Dak., Ariz., and 

 northw. (Cosmop.) 



7. A. Goldi^num Hook. Frond broadly ovate, or the fertile ovate-oblong 

 (6-10 dm. long) ; pinnae (1.5-2.3 dm. long) oblong-lanceolate, broadest in 

 the middle, pinnately parted ; the divisions {about 20 pairs) oblong-linear, 

 slightly scythe-shaped (2-3 cm. long), seri'ate with appressed teeth ; veins pin- 

 nately forliing and bearing the fruit dots very near the midvein ; indusium very 

 large, orbicular, with a deep narrow sinus, smooth and without marginal glands. 

 {Nephrodium Hook. & Grev. ; Dryopteris Gray. ) — Rich woods, centr. Me. to 

 Minn., la., and N. Car. 



Var. cfilsum (Palmer) Robinson. Fronds more narrowly ovate-oblong, slightly 

 firmer, the lowest pinnae on rather long stalks ; pinnules subremote. {Dryopteris 

 Goldieana, subsp. Palmer.) — On cypress knees and decaying logs, Dismal 

 Swamp, Va. {Palmer). 



8. A. Bo6ttli Tuckerm. Scales of the stipe pale-brown ; fronds (4-6. 5 dm. 

 long) elongated-lanceolate in outline, somewhat narrowed at base ; lowest pin- 

 nae triangular-ovate, the upper longer and narrower ; pinnules oblong-ovate, 



'Sharply .spinulose-serrate or the lower pinnatifid ; indusium minutely glandular. 

 {Nephrodium Davenp. ; Dryopteris Underw.) — Low wet thickets, etc. — Many 

 differina forms have been referred to this species. Plants corresponding to the 

 original material have been seen only from N. H., e. Mass., Ct., and" e. Pa. 

 They are suspiciously intermediate between A. cristatum and A. spinulosnm, 

 var. intermedium. 



9. A. cristatum (L.) Sw. Frond linear-ohlong or lanceolate in outline {3-i; 

 dm. long) ; piunae (5-8 cm. long) triangular-oblong, or the lowest nearly tri- 

 angular-ovate, from a somewhat heart-shaped base, acute, deeply pinnatifid ; 

 the divisions (6-10 pairs) oblong, very obtuse, finely serrate or cut-toothed, the 

 lowest pinnatifid-lobed ; fruit dots as near the midvein as the margin ; indusium 

 round-reniform, the sinus mostly shallow, smooth and naked. {Nephrodium 

 Michx.; Dryopteris Gy:a.y.) — Swamps, etc. ; common. July. — Stipes and the 

 stout creeping rootstock bearing broad and deciduous chaffy scales. (Eu.) 



Var. Clintoni4num D. C. Eaton. Frond in every way much hrrger (4-13 dm. 

 long) ; pinnae oblong-lanoeolate, broadest at base (8-15 cm. long, 2-5 cm. broad), 

 deeply pinnatifid; the divisions {S-16 pairs) crowded or distant, linear-oblong. 

 obtuse, obscurely serrate or cut-tootbed, the basal sometimes pinnately lobed ; 



