MAXON—STUDIES OF TROPICAL AMERICAN FERNS. 583 
rhizome scales are very many times larger than those of P. myriolepis and are 
ovate to deltoid-ovate, rather than suborbicular. The scales of the lower side of 
the jamina are acicular from a small subovate base and are so numerous and so 
widely imbricate as to wholly obscure the leaf surface; whereas those of 
P. myriolepis are either roundish or deltoid and acuminate, and, though so 
numerous and closely placed as to give a brownish appearance to the lamina, 
are not very widely imbricate. The sori of P. sanctae-rosae are only very 
slightly impressed; those of P. myriolepis are borne so deeply within the leaf 
tissue that the upper side of the leaf is conspicuously embossed, the pocket-like 
cavities in which the sori are sunk standing as slender raised prominences about 
1 mm. high. These particulars are not unimportant, considering the former 
eonfusion, to which reference has already been made (under P. myriolepis). 
A number of additional specimens have been received since P. sanctae-rosae 
was described, extending its known range, but not materially changing its char- 
acters. The Mexican plant cited below, determined by Liebmann as P. squama- 
tum, is somewhat atypical, differing in its more distant sori. 
The material in the U. S. National Herbarium is as follows: 
GUATEMALA: The type and two additional specimens of the type collection, 
von Tiirckheim II. 1607. Cerro Redondo, Depart. Santa Rosa, alt. 1,050 
meters, Heyde & Lux (J. D. Smith, nos, 4084, 6288). San Miguel 
Uspantin, Depart. Quiché, alt. 1,800 meters, Heyde € Lug (J. D. 
_ Smith, no. 3257). Volefin de Atitlin, Depart. Solol4, Kellerman 5789. 
Villa Nueva, Depart. Amatitlin, alt. 1,050 meters, Heyde & Lux (J. D. 
Smith, no. 4689). Fiseal, alt. 1,110 meters, Deam 6225. Near Santa 
Maria, Depart. Quetzaltenango, Kellerman 5571. 
Mexico: Hacienda de Mirador, February, 1848, Liebmann 111. 
3. Polypodium collinsii Maxon, sp. nov. PLATE 41, 
Rhizome wide-creeping, sinuous, cordlike, wholly epigean, at intervals freely 
radicose beneath (the rootlets brownish-tomentose, densély clustered), 6 to & 
mm. in diameter, irregularly sulcate, obtusely angled, smooth, but very densely 
covered with minute peltate imbricate scales, these suborbicular, 0.5 to 0.75 mm. 
broad, minutely fimbriate, reddish brown with fuscous centers, the cells short, 
subhexagonal, with sclerotic partition walls. Fronds apparently erect, 55 to 
62 cm. long. the stipe slightly shorter than the lamina; stipe about 25 cm. long, 
2.5 to 5 mn. in diameter, deeply and irregularly sulcate, smooth, very closely 
covered with minute brownish peltate scales like those of the rhizome; lamina 
30 to 85 em. long, 14 to 20 em. broad, broadly oblong or oval, scarcely or not 
at all reduced at the base, pinnatisect, abruptly short-acuminate, the terminal 
segment about 7 cm. long, nearly conform, slightly larger than those next below; 
pinne 14 to 18 pairs, slightly ascending, mostly 7 to 11 cm. long, 9 to 13 mm. 
broad, nearly linear, entire, the lower ones dilatate or slightly excised below 
and surcurrent, their own width apart, the middle and upper ones closer (the 
obtuse sinuses 4 or 5 mm. broad), fully adnate, slightly dilatate, all the pinne 
broadest in their lower third, thence gradually narrower toward the long- 
attenuate slender apex; veins oblique, immersed, atypically goniophlebioid, a 
single row of broad soriferous areoles borne upon each side of the elevated 
blackish costa, an incomplete minor row beyond, with numerous free excurrent 
branches; sori 14 to 22 pairs, large, partially immersed in the rigid coriaceous 
leaf tissue (the upper side of the pinna thus coarsely mamillose), borne mid- 
way between the midrib and margin, terminal upon the simple included veinlet 
of the areole or, commonly, the veinlet acutely once forked, both branches ex- 
tending to the sorus. Lower leaf surface bearing numerous distant pale dark- 
