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146 A NEW LASTEEA FROM ASSAM.
lowest pair of piunfe very unequal- sided, being eared (like Pteris
(juadriaurita Retz.) by prolongation of several pinnules on lower
side to 2 in. in length, these pinnules being nearly f chs of an inch
wide and piunatifid nearly to the racliis ; lowest pair of pinnules
of each pinna of lowest three-quarters of frond cordate and not
decurrent at base, and those of lowest pinnte almost stalked ; in
upper part of frond costm of lowest pinnules on lower side of pinna
springing from main and not from secondary rachis ; texture
herbaceous ; secondary rachises and costaB of pinnules pubescent,
especially above, and near main rachis clothed like it, but chiefly
underneath, with black-brown hair-like scales, replaced upwards on
pinnae by adpressed dark-brown linear glands ; costae of pinnules
and the veins above furnished also with small pale-coloured narrow
scales or glands, and the whole upper surface of lamina closely
covered with very minute short hair-like glands ; veins in upper
portion of frond all simple, 5-6 on either side of a pinnule, lower
down (where pinnules are lobed), veins of lower lobes forked ; sori
medial on the veins, and sometimes also on the veinlets ; involucres
persistent, shrivelling up from point of attachment.
This description has been written from a single specimen, consisting
of one frond, attached to a section of apes of rhizome, with
another young curled-up frond attached, which is densely clothed
with the characteristic black-brown hairs,—received from Mr.
Gustav Mann, Conservator of Forests, Assam, and collected by
him at Dighai (or Digbai), Makum Forest, Lakkimpur, Upper
Assam, in March, 1889.
The noteworthy features of the fern are the great and almost
disproportionate length of stipe, the dark-hairiness of stipe and
rachises, and the unequalsideness and compound division of the
lowest pair of pinns (if this be a constant feature), as contrasted
with the narrow shape and simple cutting of the rest of the pinnae.
The above description was sent to Mr. Mann for approval, and
in returning it without alteration he said, in a letter dated from
camp in the Garo Hills, that he was away from his collection and
should probably not return to head-quarters for five months, and
therefore could not refer to bis other specimens of the fern ; but
he said that the description was near enough, and added :— "I have
always considered it a distinct species. It is very constant, and I
have collected it in three different localities very far apart, namely
Dighai, in Upper Assam ; the southern base of the Khasi Hills,
near the Sylhet district ; and in Cachar. I have never distributed
this fern, because I considered it new, and only sent it to you.
One of the reasons why I considered it not a form of Filix-mas,^'
if these can be called so at all, is that it grows, speaking broadly,
in the plains, generally at or near the foot of hills, at no elevation,
or at any rate not more thaia about 500 ft. above the level of the
sea, whilst all the so-called forms of Filix-mas are temperate ferns,
growing at 6000 ft. altitude, and more in this part of India. I
* A well-known authority, who had seen a specimen, had named it N. Filix-
mas var.