334 Ferns of British India and Ceylon. 
13. NiPHOBOLUS NUMMULARi^FOLius. {Sw. iiuder AcrosHchuni). 
Rhizome slender wide-creeping, filiform, clothed with bright ferru- 
ginous lanceolate fibrillose scales ; fronds dimorphous, carnose-coria- 
ceous, the barren ones roundish or elliptical, subsessile inch each 
way, the ferdle ones longer and narrower, i|-2 inches long, -5-^- 
inch broad, upper surface naked, at least in age, lower densely 
coated with loose ferruginous woolly tomentum ; veins forming areoles 
irregular in size and shape, empty or with one free veinlet, marginal 
veinlets free ; sori close, scattered, sometimes covering the whole 
surface. Sw. Syn. FiL 191, 419 to 2. Polyp, nummulariaefolium. 
Mett. Farngatt Polyp. 122, /. 3. Hook. Sp. Fil. v. 54. Syn. Fil. 351. 
Bedd. F. B. I. t. 320. Galeoglossa, Presl. 
East Bengal, Bhotan, Assam, Khasya, Cachar, up to 2,500 feet 
elevation. There is a variety from Khasya (obovatum, Mett.) with 
the sterile fronds obovate on a f inch petiole. This species is 
abnormal in the genus, I do not think it is a Niphobolus at all, but 
probably a Drymoglossum. 
GENUS LXIIL—DIPTERIS. (^Reimv) 
{Di, two ; pteris, fern — the fan-like fronds in two parts.) 
Fronds adherent to the caudex, flabellate in two halves which 
are deeply lobed from their circumference in the direction of the 
base, secondary veins forming many areoles, including free or netted 
veinlets ; sori punctiform, numerous, scattered small, or in a single 
series. 
I. DiPTERis Wallichii. {Br.) Rhizome stout, creeping, 
clothed with appressed copious black hard subulate setaceous scales 
wrinkled at the back; stipes 1-2 and more feet long, smooth and 
polished, distant erect j fronds coriaceous, i-2\ feet long and much 
wider than long, dark-green above, whitish or ferruginous beneath, 
flabelliform bipartite into two nearly equal broad-cuneate portions 
which are palmately and dichotomously divided, ultimate segments 
6-10 inches long, i\-2 inches wide, oblong acuminate ; costae 
from the summit of the stipes dichotomously branched through the 
