410 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
Polypodium shaferi Maxon, sp. nov. Piate 13, B. 
Plants very small, the fronds several, ascending or subrosulate. Rhizome suberect, 
5mm. long, less than 2 mm, in diameter, much thicker from the presence of numerous 
rootlets and the bases of old fronds; scales of the rhizome inconspicuous, densely 
tufted, 1 to 1.5 mm. long, linear-oblong to oblong-lanceolate, attenuate, attached 
just above the rounded or subtruncate base, copiously long-ciliate (the cilia about 15 
upon each side, close, averaging about 0.25 mm. long, very slender, whitish-hyaline, 
spreading, often curved), 7 to 9 cells broad near the base, the cells mostly elongate, 
irregularly polyhedral, the partition walls very dark reddish brown, greatly thickened, 
in the apical part of the scale often broader than the narrow lumen; stipe obsolete or 
wanting; lamina usually linear-oblanceolate, 1.5 to 3.5 cm. long, 2.5 to 4 (rarely 5) 
mm. broad, pinnately lobed about half way to the rachis, decidedly herbaceo- 
coriaceous, at first rather freely clothed above with stiff ascending simple yellowish 
hairs, these less than 0.5 mm. long, fragile and subpersistent, the under surface more 
freely pubescent, the hairs longer, paler, softer, and spreading; lobes or segments 
monosorus, 5 to 12 pairs below the obtuse crenate apex, oblique, rounded-deltoid, 
entire, mostly about 2 mm. broad at the base, the lower ones gradually shorter and 
broader, the lowermost pair evident only as low crenations, these long-decurrent 
(2 to 4 mm.) to the base of the frond; veins mostly forked at an acute angle in their 
lower third, the proximal branch fertile below its tip; sori roundish, about 1 mm. 
in diameter, extending against the rachis, confluent at maturity; sporangia freely 
long-setose, the hairs simple; annulus with about 13 cells; spores immature. 
Type in the Underwood Fern Herbarium, New York Botanical Garden, collected 
from among moss on roots and rocks near Camp La Gloria, south of Sierra Moa, Province 
of Oriente, Cuba, December 24 to 30, 1910, by J. A. Shafer (no. 8071). Duplicate 
specimens of this collection are in the U. 8S. National Herbarium. 
Polypodium shaferi finds its nearest ally unquestionably in P. mitchellae Baker, a 
species described from British Honduras, but now known also from Nicaragua and 
Guatemala’ and, according to Christ, from Costa Rica.? It resembles that species in 
the cut of its fronds, in certain characters of its rhizome scales, and in its long-setose 
sporangia. It is very distinct specifically, however, in its lesser size, its coriaceous 
texture, its fewer, shorter, and broader lobes, its larger rhizome scales, and in the 
character and disposition of its pubescence. Young fronds in particular show many 
stifish hairs upon the whole upper surface of the frond, whereas in P. mitchellae the 
pubescence of the upper side is almost confined to the midvein and is more sparse, the 
hairs longer, and much more slender. 
The sharpest distinction between these two species, however, is observed in their 
rhizome scales; for, while the scales of both have numerous long, whitish cilia and are 
further similar in their greatly thickened, dense partition walls, they are wholly 
different in shape and size. The scales of the smaller species, P. shaferi, are elongate- 
oblong or oblong-lanceolate and measure from 1 to 1.5mm. long. Those of the larger 
species, P. mitchellae, are minute (about 0.5 mm. long) and are either broadly deltoid 
or deltoid-ovate. These differences are very clear. 
Polypodium shaferi and P. mitchellae are related to two South American species, 
P. organense (Gardn.) Mett, and P. schenckii Hieron. The last two have their rhizome 
scales similarly whitish-ciliate and with dark, greatly thickened partition cell walls; 
their sori, however, are not setose and the fronds of both are very unlike those of the 
two North American species in general appearance. Hieronymus, in describing 
P. schenckii, placed it in the small group of P. serrulatum Mett. (P. duale Maxon), but 
upon what possible ground it is hard to surmise. See page 406. 
EXPLANATION OF PLATES 13, 14.—Plate 13, type specimens of (A) Polypodium perpusillum Maxon and 
(B) Polypodium shaferi Maxon. Natural size. Plate 14, specimens of Polypodium mitchellae Baker, 
collected near Secanquim, Alta Verapaz, Guatemala, altitude 450 meters, on mossy trunk of forest tree, 
January 7, 1905, by William R. Maxon and Robert Hay (no. 3195). Natural size. 
‘Contr. U. S. Nat. Herb. 13: 43. 1909. 2 Bull. Soc. Bot. Genéve 1: 217. 1909. 
