Cyathea harrisii Underw.

Cyathea harrisii Underwood, sp. nov
Caudex erect, 1-2 meters high, 6-8 cm. in diameter, clothed at the top with glossy linear-lanceolate pale-margined castaneous scales about 3 cm. long; fronds spreading, 1.52 meters long ; stipes relatively slender, lightto dark-cas tan eons, 35-45 cm. long, bearing numerous short straight spines and clothed at the inner base and above with copious chaff like that of the caudex, above tuberculate ; lamina 1.25-1.5 meters or more long, 70-85 cm. broad, deeply tripinnatifid, chartaceous, dark -green above, paler below, the apex shortacuminate ; primary rachis lightor yellowish-castaneous, smooth below or slightly tuberculate scantily rustyfurfuraceous below, glabrescent, above more or less appressed rustypubescent ; pinnae 40-50 cm. long, 15-19 cm. broad, oblong-lanceolate, short-petiolate, the apex acuminate, the secondary rachis subflexuous, densely appressed rustypubescent above minutely pubescent or glabrate below ; pinnules 20-25 pairs, short-petiolate, oblonglanceolate, about 9 cm. long, 2 cm. broad, approximate or slightly spaced, at the base pin■ nate, above deeply piiinatifid, alate below the abruptly long-acuminate apex, the costae clothed like the secondary rachis, a small tuft of araneose-fibrillose or laciniate rusty scales at the base ; segments 16-18 pairs, 10-11 mm. long, 3.5-4 mm. broad, oblong, slightly falcate, obtuse, alternate, the lower ones slightly apart, the upper with narrow sinuses, the margins finely serrulate-crenate ; costules, veins and leaf-tissue yellowish-hirsute, especially below, the hairs partially deciduous with age, the costules bearing a few small deciduous fibrillose or laciniate ferruginous scales below ; veins 9 or 10 pairs, once-forked below the middle ; sori inframedial, ascending two thirds or less the length of the segment ; indusia very membranous, rupturing easily into irregular fragments ; receptacles elevated, slender, somewhat capitate, hirsute.
Type collected on Blue Mountain Peak, Jamaica, altitude about 2100 meters, April 21, 1903, Underwood 2502 (herb. N. Y. Bot. Card,).
Distribution : Known only from the upper slopes and summit of Blue Mountain Peak, Jamaica ; several collectors.