38 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
12. Hemitelia petiolata Hook. Sp. Fil. 1:31. 1844. 
Type Locauiry: Isthmus of Panama, Sinclair. 
Disrripution: Republic of Panama (several collectors); reported! also from the 
island of Gorgona, Colombia, 
Intustrations: Hook, loc. cit. pl. 16. 
Hooker’s short description is supplemented by so excellent a plate that there is no 
need of here redescribing the species, particularly since it is not very closely allied to 
any other. The species was observed by the writer at several localities in the low- 
lands of the Isthmus of Panama and is probably an abundant species there. The fol- 
lowing specimens are in the U. 8. National Herbarium. 
PanaMA: Near Bismark, Rk. S. Williams 512. Without definite locality, Hayes 
7. Chagres, Fendler 417. Hilly forest around the Agua Clara Reservoir, 
near Gatun, Canal Zone, altitude 20 to 30 meters, Maron 4645. Valley of 
the Masamhi, on the road to Las Cascadas Plantation, Canal Zone, altitude 
20 to 100 meters, Mazon 4684. Forest near Porto Bello, Province of Colon, 
altitude 5 to 200 meters, Maxon 5769. 
13. Hemitelia decurrens Liebm. Vid. Selsk, Skr. V. 1: 285. 1849. 
Hemistegia decurrens Fourn, Mex. Pl. 1: 135. 1872. 
Caudex 30 cm. high, or less; fronds 1 meter or more long; stipe about 30 cm. long, 
armed with short spines toward the base, above (together with the rachis) arachnoid- 
pubescent, compressed, sulcate ventrally, narrowly membranaceo-alate laterally, 
with slender scattered whitish falcate scales, or those toward the base of the stipe 
broader, more rigid, and brownish margined; lamina ovate-lanceolate, about 75 em. 
long, 20 to 23 cm. broad, simply pinnate; pinnee about 20 pairs or fewer, subopposi'e 
or alternate, narrowly oblong-lanceolate, 12 to 15 cm. long, 2.5 10 3. cm. broad, straight 
or slightly falcate, the uppermost fully adnate and confluent, those below ascending, 
unequally cuneate, constricted, semiadnate and obliquely cuneate at the upper sid>, 
obtusely and abruptly constricted below and long-decurrent, a narrow decreasing 
foliaceous wing (1 to 4 mm. broad) extending downward upon each side of the rachis 
(above) to the pinna next below; characteristic middle pinne subsessile, spreading, 
unequally and obtusely cuneate, the short petiolule distinctly foliaceo-marginate, tt.e 
decurrent wing about 2 mm, broad at origin, narrowed downward; coste elevated, 
yellowish, sparingly clothed toward the base below with whitish membranous, rounded 
or ovate, erose scales; margins remotely and lightly crenate-serrate, the teeth at the 
middle of the pinne about 6 to 8 mm. broad and | mm, long; main veins about 25 pairs 
or fewer, oblique, 5 to 9 mm. apart, clevated below, slender, with about 4 pairs of 
similar veinlets, the basal ones of adjacent groups joined by an obliquely transverse 
veinlet (forming a narrowly pentagonal elongate costal areole, cuneate proximally, 
much broader distally), then excurrent toward the margin, one or both extending to 
the minute sinus; other veinlets very oblique, nearly parallel, excurrent to the margin; 
sori few, occupying a slightly inframedial zone between the costa and the margin, in 
the partially infertile specimen at hand confined to the basal veinlets (above the areole 
and distant about 2 mm. from it) and the second pair of veinlets; indusium proximal, 
whitish, lobate, erose; leaf tissue rigidly membrano-herbaceous, lustrous above, pale 
below. 
Tyre Locauity: Mountain forests near Lobani, District of Chinantla, Oaxaca, 
Mexico, altitude 900 to 1,050 meters, Liehbmann. 
DisTRIBUTION: Known only from Oaxaca, 
The material at hand, which was received from Copenhagen, comprises a short sec- 
tion of the rachis, to which are attached the fourth pair of pinnae, With this was sent 
by Mr. Christensen a sketch of the upper pinne showing the decurrent wings which 
extend along the rachis. It is sufficient to establish the validity of the species, which 
must be reckoned one of the most peculiar in the genus, 
1 Hook. & Baker, Syn. Fil. 28. 1868. 
