16 POLYPODIACEAE 



2. Dryopteris Noveborac6nsis (L.) A. Gray. Rootstocks slender, horizontal. Leaf- 

 blades lanceolate, tapering both ways from the middle, 3-6 dm. long, membranous, long- 

 acuminate, pinnate ; leaflets lanceolate, sessile, long-acuminate, deeply pinnatifid, ciliate 

 and finely pubescent beneath, 3-7 cm. long, the two or more lower pairs gradually shorter 

 and deflexed, commonly distant ; segments flat, oblong, obtuse, the basal ones often en- 

 larged : veins simple, or those of the basal lobes forked ; sori not confluent, borne near 

 the margin : indusia minute, reniform, delicate, glandular. 



In moist or swampy woods, Newfoundland to Ontario and Minnesota, south to Georgia, Alabama 

 and Arkansas. 



3. Dryopteris Thelypteris (L.) A. Gray. Rootstocks slender. Leaf-blades lanceo- 

 late or oblong-lanceolate, scarcely narrower at the base than at the middle, 3-8 dm. long, 

 short-acuminate, membranous, pinnate ; leaflets linear-lanceolate, short-stalked or sessile, 

 mostly horizontal, acuminate at the apex, nearly truncate at the base, 3-7 cm. long, slightly 

 pubescent beneath, deeply pinnatifid ; segments oblong, obtuse, or appearing acute from 

 the strongly revolute margins : veins regularly once or twice forked : sori crowded, 10-12 

 to each segment : indusia reniform, slightly glandular, or glabrous. 



In marshes, New Brunswick to Manitoba, south to Florida and Texas. Also in Europe and Asia. 



4. Dryopteris patens (Sw. ) Kuntze. Rootstocks stout. Leaves several together; 

 blades ovate-oblong, 4-12 dm. long, softly pubescent beneath ; leaflets approximate, linear, 

 acuminate, the broadest pair somewhat reflexed, all cleft three-fourths the way to the mid- 

 rib ; segments numerous, the basal ones longest : veinlets manifest, the lowest ones of 

 adjacent segments often uniting : sori near the margins : indusia very pubescent. 



In sandy soil or on calcareous rocks, Georgia and Florida to California. 



5. Dryopteris cristata (L. ) A. Gray. Rootstocks densely chaffy. Leaves ever- 

 green ; petioles of the sterile leaves 5-12 cm. long, those of the fertile 1.5-2.5 dm. long ; 

 blades linear-oblong or lanceolate, acuminate, gradually and slightly narrowed to the 

 base, rather firm, 3-8 dm. long, pinnate ; leaflets lanceolate or triangular-ovate, acumi- 

 nate, deeply pinnatifid or the lower pinnate, the segments 6-10 pairs, serrate or incised : 

 sori about midway between the margin and midrib : indusia thin, glabrous. 



In wet woods and swamps, Newfoundland to Manitoba, south to Kentucky and Arkansas. Also 

 in Europe and Asia. 



6. Dryopteris Floridana (Hook.) Kuntze. Leaves clustered ; petioles 15-25 cm. 

 long, with few ovate scales ; blades lanceolate, 45-50 cm. long ; leaflets various ; fertile 

 confined to the upper half of the leaf-blade, narrowly lanceolate, cut nearly to the rachis 

 into oblong segments ; sterile leaflets broader, shorter below, less deeply cut. 



In swamps, Georgia, Florida and Alabama. 



7. Dryopteris Goldieana (Hook. ) A. Gray. Rootstocks chaffy. Petioles 2.5-4.5 

 dm. long, chaffy at least below ; leaf-blades ovate, rather firm, 6-12 dm. long, glabrous or 

 nearly so, dark -green above, pinnate or nearly 2-pinnate ; lower leaflets broadly lanceolate, 

 widest at about the middle, 1.5-2.5 dm. long, parted into about 20 pairs of oblong-linear 

 subfalcate segments which are serrate with appressed teeth : sori very near the midrib, 

 close together but distinct, large : indusia orbicular, glabrous, persistent. 



In rich woods, New Brunswick to Minnesota, south to North Carolina and the Indian Territory. 



8. Dryopteris marginalia ( L. ) A. Gray. Rootstocks ascending, with dark brown 

 shining scales. Leaves evergreen ; petioles 7-20 cm. long, chaffy below ; blades ovate- 

 oblong or ovate-lanceolate, rather leathery, 1.5-7.5 dm. long, 1-2-pinnate, acuminate at 

 the apex, slightly narrowed at the base ; leaflets numerous, lanceolate, nearly sessile, gla- 

 brous, 5-12.5 cm. long, the lower broader and shorter than the middle ones, the upper 

 pinnatifid, the lower pinnately parted into oblong obtuse entire dentate or pinnately lobed 

 segments : sori distinct, close to the margin, covered by the glabrous indusia. 



In rocky woods, Prince Edward Island to Minnesota, south to Georgia, Alabama and Arkansas. 



9. Dryopteris spinulosa (Retz) Kuntze. Leaves tufted, evergreen ; petioles bearing 

 scales with dark centers ; blades ovate-lanceolate, usually not narrowed below, 2-pinnate ; 

 leaflets narrowly triangular or the lower pairs broadly triangular, the ultimate segments 

 oblique,' connected by a very narrow wing, with spinulose-toothed lobes : indusia glabrous. 



In rich woods, Newfoundland to Alaska and Washington, south to Virginia and Michigan. Also 

 in Europe and Asia. Summer. Two forms represent the species in our range : one, D. spinulosa inter- 

 media (Muni.) Underw., has oblong-ovate 2-3-pinnate leaf-blades and oblong-lanceolate spreading 

 leaflets, the lowest unequally triangular-ovate : indusium beset with stalked glands. Its range extends 

 southward to North Carolina and Missouri. The other variety. D. spinulosa dilatata (Hoffm.) Underw.. 

 with broadly ovate or triangular-ovate commonly 3-pinnate blades, lanceolate-oblong ultimate divi- 

 sions, the lowest often much elongated, and glabrous indusia, ranges as far sonth as Georgia, Tennessee 

 and Nebraska. 



10. Dryopteris unita (L. ) Kuntze. Leaves tufted ; petioles brownish, naked, about 

 45cm. long; blades 0.5-1 m. long, 12-20 cm. wide; leaflets narrow, the lower ones not 

 reduced, cleft to J the way to the midrib ; segments acute : veins pinnate in the broad 



