CHARACTERS OF TRIBES AND GENERA. 99 
Oss.— Representatives of this genus are widely spread 
over the Eastern hemisphere, extending from New Zealand 
and Australia to the Polynesian and Malayan islands, Japan, 
India and South Africa, but none as yet have been observed 
in the Western hemisphere. 
15. Nnm, J. Sm. 
Polypodium sp., auct; Hook. Sp. Fil. 
Surculum thick cwspitose. Fronds stipate, linear lanceo- 
late 13 to 2 ft. long, attenuated, firm coriaceous, the upper 
side smooth and glossy, the under side densely stellato- 
tomentose. Primary veins straight oblique. Receptacles 
compital, forming a row (of about four) of large oval sori, 
between each pair of primary veins. 
Type. Polpodium americanum, Hook. 
Oss.— The only representative of this genus is a native 
| of Ecuador and Quito, observed by Dr. Jameson and Spruce, 
from whom Sir Wm, Hooker received specimens, and 
I possessed a specimen of it collected by Hartweg. In 
general appearance it resembles narrow fronds of Pleuri- 
dium crassifolium, with which it also agrees in the sori 
being large and in an oblique row between the primary 
. veins, but differs in the under side being densely stellated 
tomentose, as in Niphobolus but from which it differs in 
having oblique uniserial sori, which also distinguishes it 
— from Niphopsis. 
—. Sp. N. americana, J. Sm., Hook. 
CR 16. Corxsis, Presl, (1849.) 
Polypodium sp. Gymnogramma sp. auct. and Hook. Sp. Fil. 
- Surculum short, sub-hypogeous. Fronds simple, lobed or 
tifid, generally membraneous, flaccid, 1 to 3 feet long. — 
d ree 
