72 NORTH AMERICAN FLORA [VoLtumE 16 
9. Cyathea portoricensis Spreng.; Kuhn, Linnaea 36: 163. 1869. 
Caudex undescribed; fronds ample, the lamina nearly tripinnate, subcoriaceous, the 
leaf-tissue dark-green above, paler below and somewhat yellowish; stipe dark purplish- 
brown, toward the base armed with slender curved shining purplish spines, slightly muricate 
above, somewhat rusty-furfuraceous and sparingly clothed with flaccid fibrillose lacerate 
scales, these mostly deciduous; primary rachis similar in color, soon glabrescent, shining; 
pinnae subsessile or short-petiolate, oblong, rather abruptly acuminate, up to 65 cm. long 
and 21 cm. broad, the secondary rachis stont, similar to the primary, densely rusty-pilose 
above; pinnules approximate, 20-25 pairs, nearly equal, up to 10.5 cm. long, 2-2.5 cm. 
broad, sessile, elongate-oblong, acuminate, the costa rusty-pilose above, below sparingly 
dull whitish-pilose and toward the base bearing a few reduced brownish lacerate scales ; 
segments about 20 pairs, oblique, 10-13 mm. long, about 3 mm. broad, elongate-oblong, 
obtuse, regularly crenate, the basal ones somewhat apart aud sessile, those above dilatate 
but distinct, only the apical ones slightly connected; costules hairy below and minutely 
paleaceous like the costae; veins about 8 pairs, mostly once-forked below the middle, the 
branches widely divergent or the outer sterile ones 2 or (rarely) 3 times forked, these to- 
gether with the under surface of the leaf-tissue rather densely clothed with dull whitish 
hairs; sori slightly inframedial, 3-6 pairs; indusium deeply cyathiform, yellowish-brown, 
chartaceous, densely covered with subpersistent simple yellowish-white hairs; receptacle 
slender, elongate, nearly equaling the even margin, obconical or slightly capitate, dark- 
brown, setiferous. 
TYPE LOCALITY: Porto Rico. 
DISTRIBUTION: Known only from the mountains of eastern Porto Rico. 
10. Cyathea crassa Maxon, Contr. U.S. Nat. Herb. 13: 40. 1909. 
Caudex erect, 3-8 meters high, spiny ; stipe undescribed ; rachis (at least in the upper 
part) castaneous, polished, glabrous; pinnae dark-green above, paler below, coriaceous, 
deltoid-lanceolate, 40-60 cm. long, 15-22 cm. broad, sessile, with about 16-20 pairs of pin- 
nules below the abruptly acuminate apex, the secondary rachis brownish-castaneous, 
glabrous and shining on the under surface, above deeply sulcate, minutely dark-pilose, and 
with a few scattering minute castaneous stellate scales; pinnules contiguous or slightly 
apart, oblong to deltoid-oblong, 8-11.5 cm. long, 2-4 cm. broad at the base, sessile or 
essentially so, cut nearly or quite to the costa, the apex long-acuminate, serrate-crenate ; 
segments 13-17 pairs, approximate or slightly apart, oblong, subfalcate, slightly oblique, 
obtuse, mostly adnate, the middle and lower ones decurrent, only the basal ones sessile, 
these the largest (up to 2 cm. long and 8 mm. broad), deeply inciso-pinnatifid (the lobes 
pinnately veined, sometimes with 2 basal sori), those above deeply inciso-crenate, the 
uppermost dentate-serrate ; costae, costules, veins, and surfaces glabrous below; veins 
(excepting those of the basal segments) 1~3-forked, 6-8 pairs, mostly fertile; sori near the 
costule, large, distant ; indusium castaneous, deeply hemispheric, rigidly coriaceous, per- 
sistent ; receptacle capitate, somewhat hirsute, glabrescent, slightly included. 
TYPE LOCALITY: Forests of Mount Izabel de la Torre, Santo Domingo, altitude 550 meters. 
DISTRIBUTION : Known only from the type locality. 
11. Cyathea elegans Hew. Mag. Nat. Hist. II. 2: 466. 1838. 
Cyathea arborea pailida Hook. Sp. Fil.1: 17. 1844, 
Caudex erect, 3-7 meters high, 5-10 cm. in diameter, densely covered (especially in 
smaller plants) with old stipe-bases, the eventual scars rough with projecting fibrovascular 
bundles; stipe 10-30 cm. long, 2 em. in diameter at the base, dark-brown, minutely 
puberulo-furfuraceous, bearing on the under surface a few deciduous subulate glossy dark- 
brown scales and armed with a few short long-pointed curved spines, and commonly bear- 
ing also a pair of abortive pinnae; lamina ample, 2-3 meters long, 90-130 cm. broad, char- 
taceo-coriaceous, tripinnate, dark-green, the rachis pale-brown, puberulous, smooth or 
below somewhat muricate, the secondary rachises similar; pinnae approximate, oblong- 
lanceolate, 45-70 cm. long, 15-22 cm. broad, sessile or the lowermost short-stalked (1-1.5 
