FILICES. (FERNS.) 595 



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

 ure ; the pinnae fewer and set farther apart, the lowest pair largest, with the 2-3 

 lower basal pinnules elongated ; segments larger and more distant ; fruit-dots 

 larger ;. indusium smooth. (A. dilatatum, Swartz. A. campylopterum, Kunze.) 



Summits of the Black Mountains, North Carolina, Ruyel. Fronds l-2 

 long, .10' -16' wide. 



5. A. Lud.OViciEHU.ID., Kunze. ' Fronds membranaceous, rather rigid, 

 finely glandular-pubescent beneath on the midribs, ovate, acuminate, bipinnate ; 

 pinnae distant, petioled, ovate or oblong, acuminate ; pinnules ovate, deeply 

 pinnatifid ; the lowest divisions sessile with a narrowed base ; the upper ones 

 adnate, oblong, obtuse, crenately appressed-serrate ; serratures acute, sometimes 

 denticulate ; fruit-dots half-way between the midrib and margin, on the upper 

 branches of the forked veins ; indusium reniform, thickish, entire, smooth, per- 

 sistent." Mettenius. Florida to Louisiana, Kunze. " Rootstock oblique ; 

 fronds 2 -3 long; stipe straw-color, sparsely chaffy" I have not seen this 

 Fern, which has more recently been referred by Mettenius to A. Canariense, 

 At. Br. 



6. A. Floridanum. Fronds thickish, broadly lanceolate, pinnate ; lower 

 pinnae sterile, triangular-lanceolate, deeply pinnatifid, with closely set oblong, 

 obtuse divisions ; upper pinnoa 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.) Wet woods, Florida to Louisiana. 



Fronds l-2 high, the sterile ones shorter, growing in a crown from a 

 thick and scaly rootstock. The plant has much the appearance of large 

 forms of A. cristatum, Su/artz, and may prove to be an extreme state of that 

 species. 



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

 most coriaceous, ovate-lanceolate, bipinnate ; pinnae 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, 

 very near the margin ; indusium round-reniform, convex, thickish, smooth. 

 Mountains of North Carolina, and northward. Fronds bluish-green, l-2 

 long, on a short stipe, which, like the short thick rootstock, is shaggy with large 

 brown chaffy scales. 



2. POLYSTICHUM, Roth, Schott. Indusium orbicular, fixed by the de- 

 pressed centre. 



8. A. acrostichoides, Swartz. Fronds evergreen, thickish, smooth and 

 shining, lanceolate, the fertile ones tallest, pinnate ; pinnae numerous, short- 

 stalked, oblong-lanceolate, auriculate at the base on the upper side, cuneate at 

 the lower, obtuse or acute, finely serrate or incised with spinulose-pointed teeth ; 

 the upper pinnae of the fertile frond contracted and covered with the copious 

 fruit-dots ; indusium round, peltate, smooth and entire. Shady and rocky 

 woods, Florida to Mississippi, and northward. Fronds l-2 high. Root- 

 stock and stipe very chaffy. 



