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328 THREE NEW LASTREAS FROM ASSAM.
the lowest pair of pinntB, seldom ou the lower 8-6 pairs, and
are sometimes confined to the upper part of the frond. I have had
difficulty in naming this plant, owing to the absence of any very
striking features, and to there being already a Ncphrodium (Lastrea)
lati/runs Hook, and a Nejfhrodiitm (Sagen.) latifulium Baker.
Nephrodium (Lastrea) coriaceum, n. sp. — Caudex erect
stipes closely tufted, stout, 5-12 in. long, thickly clothed with long
linear hair-pointed dark chestnut scales at and near the base, and
above, together with main rachis, closely covered with minute
raised darli-coloured points, the scars of scales which quickly fall
off; racMses rather densely furnished with dirty-brown hair-like
scales with adpressed ovate bases; frond lanceolate-deltoid, acuminate,
9-15 in. long by 6-10 in. broad, subbipinnate, with 8 or 9
pairs of quite free pinnae, and 20-25 pairs of small sessile falcate
pimife rapidly diminishing to mere lobes in the pinnatifid apex ;
lowest pinme the longest, and at the base widened on the inferior
side by the prolongation of one or more pairs of pinnules ; ;*m?i®
diminishing in width regularly to apex, but lowest pair of pinnules
much longer than next above, and inferior pinnule of that pair
longer and broader than the superior, and more out of proportion
on each successive i^inna towards the base of the frond ; secondary
pinna catadromous, except on lowest pair of pinnae, where they
become anadromous owing to the omission (for want of room) of
lowest inferior pinnules piniKB more and more deeply cut into
;
segments downwards from confluent apex to base until ]>air next
main rachis become quite free, cordate and stalked pinnules ; in
large fronds two pairs of pinynUes on two lowest pairs of pinnse free,
and these disproportionately long, inferior ones being 2-|— 3-|- in.,
and becoming compound at base ; segments of jnnncB broadly falcate,
rounded to a sharp point, and in upper parts of frond and pinna)
usually entire to near the pomt, where they are slightly serrated,
in large fronds pinnules or segments of pinnae crenate on sides,
lowest enlarged ones becoming pinnatifid, like the smaller pinnae
texture very thick, coriaceous, and tough, with lamina sometimes
opaque; colour pale greyish green, upper surface glabrous, costa)
and veins below squamiferous ; veins obscurely traceable above,
slightly raised below, more or less visible against light, forked to
pinnate ; son on inner veinlet of each group of veins, but not
extending to apices of segments, submarginal, and in the enlarged
pinnules of compound fronds appearing to be at sinus between the
lobes, with rarely one more on upper edge of lobes ; involucres^
when not shrivelled, apparently orbicular.
Collected by Mr. Gustav Mann, Conservator of Forests, Assam,
at Kopili Hot Springs, North Cachar Hills, Assam, at 1000 ft.
elevation, February, 1890. Three pairs of mature fronds received,
two of which have one barren and one fertile frond each, the stipes
of the barren fronds being only half to three-quarters as long as
those of the fertile, and the barren fronds bemg less compound.
The ears, or enlarged i^innules, are parallel to the other pinnules,
not deflexed. The plant seems quite unique in its genus, so far as
Indian ferns go, the texture and cutting reminding one of small