20 POLYPODIACEAE 



Indusia wanting. (5 Phegopteris.) 16. D. hexagonoptera. 



Basal 1 or 2 pairs of adjacent groups of veins joined. 

 Indusia present. (§ Cyclosorus.) 



Leaflets cut one-half or less the distance to the midrib; segments 



triangular. 17. D. gonglyodes. 



Leaflets cut three-fourths or more the distance to the midrib; seg- 

 ments oblong. 18. D. parasitica. 

 Indusia vestigial or wholly wanting. (§ Goninpieris.) 



Fertile leaves of two sorts, one rigid and pinnatifid toward the apex, 



the other pinnate throughout, lax and proliferous. 19. D. radicans. 



Fertile leaves of one sort, with a large terminal leaflet. 20. D. tetragona. 



1. Dryopteris Panain6nsis (Presl) C. Chr. Kootstocks erect, 2-4 dm. high. 

 Leaves in a close crown; petioles short, 4-10 cm. long, scaly at base; blades 3-12 dm. 

 long, lanceolate, narrowed at the base; leaflets very numerous, sessile, narrowly lance- 

 olate from a broader base, acuminate, deeply pinnatifid, the middle ones 7-12 cm. long, 

 the lowest greatly reduced, hastate, distant; segments obtuse, oblique falcate, acutish, 

 entire; veins simple, 7-9 pairs; sori near the margins: indusia minute, ovate-reniform, 

 glandular and slightly pilose, evanescent. [D. contermina of most authors, in part.] 



In swamps near Fort Meade, Florida. Also in tropical America. 



2. Dryopteris No veborac6usis (L.) A. Gray. Kootstocks slender, wide-creep- 

 ing. Leaf -blades lanceolate, tapering both ways from the middle, 3-6 dm. long, mem- 

 branous, long-acuminate, pinnate; leaflets lanceolate, sessile, long-acuminate, deeply 

 pinnatifid, ciliate, pilose on the midribs and veins, especially beneath, 3-7 cm. long, 

 the lower ones gradually shorter and deflexed, distant; segments flat, oblong, obtuse, 

 the basal often enlarged: veins simple, or those of the basal lobes forked; sori near 

 the margin, not confluent: indusia minute, delicate, glandular. 



In low woods, Newfoundland to Ontario and Minnesota, south to Georgia, Alabama 

 and Arkansas. 



3. Dryopteris Thelypteris (L.) A. Gray. Eootstocks slender, creeping. Leaf- 



blades lanceolate or oblong-lanceolate, scarcely narrowed at the base, 3-8 dm. long, 



short-acuminate, membranous, pinnate; leaflets linear-lanceolate, broadest at the 



short-stalked or sessile base, mostly horizontal, acuminate, 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 nearly 



medial, crowded : indusia small, glabrous. 



In marshes and low woods, New Brunswick to Manitoba and the Gulf States. Also in 

 Europe and Asia. 



4. Dryopteris stipul^ris (Willd.) Maxon. Eootstoek stout, erect, up to 1 dm. 



high. Leaves clustered, arching; petioles 3-6 dm. long, stout, scaly at the base; 



blades 4-7 dm. long, 2-4 dm. broad, narrowly ovate, 2-pinnatifid, papyraceous, more 



or less pubescent; leaflets spreading, sessile, close, linear, cut about * the distance to 



the midrib, the lowest pair or two somewhat smaller and deflexed; segments close, 



subfalcate, the superior (and sometimes the lower) basal segments of the lower 



leaflets greatly enlarged (1-3 cm. long, 0.5-1 cm. broad), deeply incised, with several 



pairs of segments; veins 8-15 pairs, simple, free: sori medial: indusia large, pilose. 



In crevices of limestone, in hammocks, southern peninsular Florida. Also in tropical 

 America. 



5. Dryopteris patens (Sw.) Kuntze. Eootstocks creeping, woody. Leaves 



erect, in two rows ; blades ovate-oblong, 4-15 dm. long, more or less pubescent 



throughout; leaflets approximate, linear-lanceolate, broadest at the base, acuminate, 



the lowest scarcely reduced, all cleft two thirds or more the way to the midrib; 



segments numerous,, close, oblong, entire; veinlets 6-11 pairs, free, simple, close, 



very oblique: sori near the margins: indusia very pubescent. 



In swamps, rich wet woods and calcareous sinks, Georgia and Florida to Texas. Also 

 in California and tropical America. 



6. Dryopteris dmpla (H. & B.) Kuntze. Eootstoek erect, often 4-5 dm. high, 

 clothed with delicate wool-like rusty scales. Leaves widely arching; petioles fascicu- 

 late, 4-8 dm. long, densely clothed at the base like the rootstock, above with minute 

 appressed scales; blades deltoid, 3-7 dm. long, nearly as broad, 4-pinnatifid or 

 3-pinnatifid above ; lower divisions much the largest, stalked, unequally deltoid, the 

 secondary pinnae unequally oblong-lanceolate, acute; ultimate segments linear-oblong, 

 entire to crenately incised: sori small: indusia minute, fugacious. 



In hammocks, southern peninsular Florida. Also in tropical America. 



7. Dryopteris setigera (Blume) Kuntze. Eootstoek stout, creeping or ascend- 

 ing, clothed with long ciliate dark lirown scales. Leaves 8-10; stipes up to 6 dm. 

 long, chaffy at the base; blades deltoid-ovate, 7-9 dm. long, 4-pinnatifid, the primary 



