594 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
thicker than the castaneous outer walls). It resembles P. squamatum somewhat 
in leaf shape, but it is a much more rigid plant, with stout, deeply sulcate, 
divaricately paleaceous stipes and more numerous pinne, these with conspicu- 
ous, rigid, wide-spreading, subcapillary, fulvous scales. It is related also to 
P. rosei, but differs widely in its scales, as also in stature and general appear- 
ance. The wide-creeping, branched, woody rhizomes, with numerous prominent 
knoblike, shallowly cyathiform phyllopodia, are wholly characteristic. 
The following specimens of P. pyrrholepis are in the U. S. National 
Herbarium: 
Mexico: Vicinity of Cérdoba, Veracruz, Fink 74 (4 sheets), 78 tn part. 
Tezonapa, Veracruz, Orcutt 3375. Zacuapan, Veracruz, January, 1906, 
Purpus 2166. Orizaba, Mohr “ 20, 30, 32.” 
15. Polypodium rosei Maxon sp. nov. 
Rhizome creeping, simple or with a few short branches, 2.5 to 5 mm. in 
diameter, freely radicose beneath, densely paleaceous, the scales 3 to 6 mm. 
long, 0.6 to 0.9 mm. broad, linear-deltoid, mostly long-attenuate, variable in 
color, richly castaneous with age, the cells of the basal part mostly small, 
short or oblong-hexagonal, with thick, highly colored partition walls and hya- 
line to castaneous outer walls, the lumina open or inclosed; margins with 
numerous, close, mostly divergent, cylindrical teeth, these averaging about 0.13 
mm. long, cleft half their length or less. Fronds several, ascending, 15 to 80 
em. long, arising 0.5 to 8 em. apart, densely paleaceous throughout; stipes 
2.5 to 8 em. long, arcuate; lamina linear-oblanceolate to linear-oblong, 10 to 
25 cm. long, 3.5 to 6 em. broad, subpinnatisect, acute, caudate, rather abruptly 
narrowed in the basal third (the 1 to 3 lowermost pairs of segments 0.5 to 
2 cm, long) or not at all reduced; segments 15 to 20 pairs, their own width 
apart or more, spreading, mostly 2 to 8 cm. long, 3 to 5 mm. broad, linear, 
acute, widely dilatate (sometimes bearing a minute distal auricle), connected 
by a narrow wing, the sinuses broad, rounded-obtuse; scales of the lower sur- 
face of segments very dense, widely imbricate, buff to reddish brown in mass, 
dark-centered, 1 to 2.5 mm. long, deltoid-ovate and acuminate-attenuate or 
rounded and rather abruptly subulate, the basal portion bearing numerous, 
very long, closely set, divergent, slender, deeply once cleft teeth, similar but 
shorter and oblique teeth borne also toward the apex; scales of the upper side 
whitish, fewer, smaller, nearly capillary, with long spreading teeth; venation 
concealed, goniophlebioid, a single row of 7 to 13 angular-oval areoles extend- 
ing more than halfway to the margin, the excurrent veinlets free or partly 
joined in a minor series; sori 6 to 12 pairs, small, slightly inframedial, super- 
ficial, terminal upon the short simple included veinlets, evident at maturity. 
Leaf tissue yellowish green above, rigidly herbaceous. 
Type in the U. 8. National Herbarium, no. 450839, collected from cliffs of 
the Sierra de Tepostlin, State of Morelos, Mexico, September 21, 1903, by 
J. N. Rose and Joseph H. Painter (no. 7254). 
Scarcely to be confused with any other species of Mexico, unless perhaps with 
small specimens of P. pyrrholepis, from which it differs widely in its rhizome 
scales, these (though variable) being flaccid, imbricate, and distinctly linear- 
deltoid; whereas those of P. pyrrholepis are rigidly divergent and almost 
capillary, being abruptly attenuate-acicular from a small rounded or subovate 
base. The scales of the lamina show differences almost equally great. 
Polypodium rosei is not very unlike small plants of P. squamatum in leaf 
form, but it differs very plainly in most of the minute characters, notably in 
scale shape and structure, and in having superficial rather than impressed sori. 
P. squamatum is wholly West Indian. 
