632 riLicKs. (fekxs.) 



veins simple, free, or tlie basal ones meeting at the sinus liotwoen tlie seg- 

 ments; iiulusium small, puhesoont. — Low shady woods, Florida to Soutli 

 Carolina, and westward. — Fronds l°-3° higii. 



4. A. conterminum, Willd., var. strigosum, Katon. Kootstock 

 thick, erect; stipe short and scaly; frond li'^-3° higli, ohloug-lanceolate, 

 attenuate at each end, ])innate ; pinnjc very numerous, lanceolate, acuminate, 

 sessile, pinnatifid, tiie lower ones gradually reduced, the segments ohliipiely 

 acute, the lowest ones often elongated; sori small, in a single marginal row. 

 — Polk County, Florida (./. D. Smith). 



5. A. unitum, var. glabrum, Mettonius. Stipe long and slc-nder, 

 from a slciidt-r creeping rootstock ; frond rather rigid, siiioijth, ovale-Iance- 

 olate, pinnate, l^°-2° long; pinnte lanceolate, pinnatirtd-lohed, tiie lobes 

 rounded ; lower veins of contiguous lobes united ; sori forming a continuous 

 zigzag intramarginal line. — Boggy places, South Florida. 



* * Fronds thicker ; ultimate se(/ineiits more or less serrate or toothed ,• the lowest 

 veins more than once forked. 



6. A. spinulosum, Swartz. Frondsovate-oblong, thin, smooth; bipin- 

 nate or below tripinnate ; pinnte oblong-lanceolate ; the lower ones broader, 

 triangular-ovate; ultimate segments oblong, or linear-oblong, closely set on a 

 narrowly winged partial rachis, variously incised or serrate with spinulose 

 teeth ; fruit-dots small ; indusium deciduous, sparingly glandular at the 

 margin. (A. intermedium, Muhl.) — Shady woods in tiie upper districts. — 

 Fronds l°-2° long, 5' -9' wide, varying greatly in outline, and in the shape 

 of the segments. 



Var. dilatatum, Gray. Fronds wider in outline, of a rather firmer tex- 

 ture ; the pinnaj fewer and set fartlier apart, the lowest pair largest, with the 

 2-3 lower basal pinnules elongated; segments larger and more distant; 

 fruit-dots larger ; indusium smooth. — Summits of tlie Black Mountains, 

 Xorth Carolina [Rugel). — Fronds l°-2° long, 10'- 16' wide. 



7. A. Goldianum, Hook. Frond broadly ovate, 2° -4° high: pinna; 

 oblong-lanceolate, deeply pinnatifid. 6' - 9' long, the segments oblong-linear, 

 sliglitly falcate, sharply serrulate ; fruit-dots small, arranged in a row on each 

 side of the midvein ; indusium large with a narrow sinus. — Low woodlands, 

 Tennes.see, and northward. 



8. A. Floridanura, D. C. Eaton. Fronds thickish, broadly lanceolate, 

 pinnate ; lower pinna; .sterile, triangular-lanceolate, deeply pinnatifid, with 

 closely set oblong obtuse divisions; upper pinnaj fertile, narrower and longer, 

 again pinnate, with oblong obtuse pinnules, distant on the narrowly winged 

 secondary rachis ; fruit-dots large, half-way between the midrib and margin ; 

 indusium round-reniform, smooth. (Nephrodium Floridanum, Hook.) — AVet 

 woods, Florida to Louisiana. — Eronds 1°- 2° high, the sterile ones shorter, 

 growing in a crown from a thick and scaly rootstock. 



9. A. marginale, Swartz. Fronds evergreen, smooth, thickish and al- 

 most coriaceous, ovate-lanceolate, bipinnate ; pinniB lanceolate from a broad 

 base ; pinnules oblong or linear-oblong, attached by a broad base to the nar- 

 rowly winged secondary rachis, entire or crenately toothed ; fruit-dots large, 



