74 NORTH AMERICAN FLORA [VoLumE 16 
gradually in the upper third to a long-acuminate crenate-serrulate apex ; segments 22-24 pairs, 
10-12 mm. long, 44.5 mm. broad, oblong, straight or subfalcate, obtuse, the lowermost 
somewhat apart and sessile, those above adnate and mostly connected by a narrow wing, 
the margins crenulate-serrulate, at least toward the apex; costae yellowish, glabrate above, 
below sparsely and deciduously paleaceous, the scales small, yellowish or brownish, fimbriate, 
with larger narrower dark scales intermixed, especially toward the base; costules naked 
above, below sparsely paleaceous and sometimes slightly hairy in the outer part, the scales 
yellowish or brown, flattish ; veins 9-11 pairs, once- or frequently twice-forked near the 
base, dark ; sori close to the costule, 2-4 (5) pairs, usually at the base of the segment; 
indusium deeply hemispheric, pale-brownish, collapsing at maturity ; receptacle large, setif- 
erous, scarcely or not included. 
Type collected on the slopes of El Yunque, Cuba, altitude 500-600 meters, March, 1903, Under- 
wood & Farle 1313. 
DISTRIBUTION: Common throughout the partially forested mountains of eastern Cuba, alti- 
tude 400 to 625 meters. 
14. Cyathea nigrescens (Hook.) J. Smith, Ferns 
Brit. & For. 242. 1866. 
Cyathea arborea nigrescens Hook. Sp. Fil, 1:17. 1844. 
Caudex erect, 1-3 meters high, 10-12 cm. in diameter, long-spinescent and rough with 
bases of the slowly deciduous fronds, the stipe-scars rough with protruding fibrovascular 
bundles; stipe stout, 45-60 cm. long, 3 cm. in diameter at the base, dark purplish-brown, 
scurfy, armed with numerous stout purplish-black spines 1 cm. or less long and bearing 
copious rigid dark-brown shining deciduous scales at the base; lamina up to 2 meters long, 
1-1.25 meters broad, tripinnate, rigidly coriaceous, above dark-green, below paler and some- 
what glaucous, the rachis dark- or purplish-brown, lucid, puberulous, smooth or slightly 
muricate below, spinescent above; pinnae approximate, 45-65 cm. long, 15-20 cm. broad, 
lanceolate, sessile or the lower ones short-stipitate, the apex deeply serrate-acuminate; sec- 
ondary rachis smoothish or slightly muricate below, dark purplish-brown, sparingly furfu- 
raceo-paleaceous, glabrescent, above sulcate and densely hirsute with appressed brownish 
hairs, 4 few slender scales intermixed; pinnules about 30 pairs, approximate or slightly 
spaced, subsessile or the inferior short-stalked, 3-9 cm. long, 1.5-2 cm. broad, lanceolate, 
at the base fully pinnate, above cut almost to the costa, the apex acuminate-serrulate ; 
costae yellowish-brown, brownish-strigose above, below yellowish, furfuraceo-paleaceous, 
glabrescent; segments about 20 pairs, 9-10 mm. long, narrowly oblong, falcate, obtusish, 
the lowermost spaced and sessile or short-stalked, those above adnate, the margins entire 
and strongly revolute; costules glabrous above, below paleaceous, especially toward the 
base, the scales yellowish-brown, bullate, deciduous, with occasional yellowish hairs inter- 
mixed and toward the apex; veins distinct, about 10-12 pairs, mostly once-forked near the 
base; sori close to the costule, usually 1 or 2 pairs, confined to the base of the segment, 
rarely several pairs ascending to the middle or beyond; indusia deeply hemispheric, brown- 
ish, membranous, persistent ; receptacle stout, setiferous, scarcely included. 
TYPE LOCALITY : Jamaica. , 
DISTRIBUTION: Confined to Jamaica; not uncommon in wooded and open situations in the 
central and western portions at altitudes of from 700 to 1500 meters. 
15. Cyathea araneosa Maxon, sp. nov. 
Caudex 3-4 meters high, very thick, densely covered with old stipes, rough and very 
spiny; stipe 30 cm. or more long, 2 cm. or more in diameter, dark-brown, deciduously 
furfuraceous, dark-paleaceous at the base and with numerous stout straight or slightly 
curved purplish-brown conical spines 7 mm. or less long, the rachis similar but smooth or 
muricate below, the reduced slender spines borne at the sides above ; lamina 2 meters or more 
long, about 110 cm. broad, tripinnate, exceedingly coriaceous, brittle, lurid-green above, 
paler and glaucous below; pinnae alternate, approximate, 50-55 cm. long, 13-15 cm. broad, 
lanceolate, sessile, the apex short-acuminate; secondary rachis brownish below, slightly 
roughened and obscurely furfuraceous, glabrescent, above lighter, striate, densely covered 
