MAXON—STUDIES OF TROPICAL AMERICAN FERNS. 595 
The following additional specimens of P. rosei are in the U. S. National 
Herbarium: 
Mexico: Near El Parque, Morelos, Rose € Rose 11117. Hills near Guadala- 
jara, Jalisco, on ledges and trees, Pringle 4535 (2 sheets). 
16. Polypodium squamatum L. Sp. Pl. 1086. 1753. 
Marginaria squamata Presl, Tent. Pter. 188, 1836. 
Goniophlebium squamatum Moore, Ind. Fil. 391. 1862. 
Drynaria squamata Fée, Mém. Foug. 11: 72. 1866. 
Pleopeltis squamata J. Smith, Hist. Fil. 114. 1875. 
TYPE LOCALITY: Jamaica. 
DistrRIBuTION: Jamaica and Porto Rico, ascending to 1,600 meters. 
ILLUSTRATION: Plum. Trait. Foug. pl. 79. 
Polypodium squamatum was founded by Linnzus upon the “ Polypodium 
longifolium, squamulis argenteis” of Petiver. Petiver’s illustration (pl. 7. f. 
11) is obviously redrawn from Plumier’s plate 79, depicting in exaggerated 
form a Jamaican plant. Authors from that time to the present have included 
in their concept of P. squamatum several different species from the American 
mainland (Christensen’s Index, for example, giving the range “Ind. oce. 
Mexico-Peru), although material at hand shows clearly that this is a species 
confined to the West Indies. The “P. squamatum” of Mettenius* is prob- 
lematical; that of Liebmann is, at least in part, P. sanctae-rosae. 
The most dependable character of P. sguamatum, leaving out of consideration 
the unmistakable and distinctive facies of the plant, lies in the form and 
color of its rhizome scales. These are 3 to 4 mm. long; the basal third is 
broadly ovate, the apical two-thirds long-acuminate and very gradually attenu- 
ate to a hairlike point. Only the extreme lacerate-fimbriate border of the scale 
is pale and transparent, the entire median portion being dark reddish-casta- 
neous. The partition walls of the median cells are, apparently, no thicker 
than in several related species; but both they and the outer walls are so richly 
colored that the lumina are nearly or quite obscured. The castaneous scale 
thus appears to have a darker, broad, median band nearly throughout. The 
rhizome scales of P. pyrrholepis also are highly colored, but they are smaller 
and of very different shape, being more abruptly attenuate from a roundish 
base. The lamina seales of the two species also are widely different, as ex- 
plained under P. pyrrholepis. 
Jenman attempted to distinguish two forms in Jamaica, under the names 
P. squamatum and P. lepidopteris, upon the basis of texture, dwarfing of basal 
segments, and color of lamina scales; but these must needs be variable char- 
acters in a plant extending from the lowlands to 1,600 meters altitude, occur- 
ring indiscriminately on exposed banks and ledges and upon rotten branches 
of forest trees; and the whole series of specimens here cited is believed to 
represent but a single variable species. The resemblance of any of them to 
the Brazilian P. lepidopteris must be called remote; it is true that 1 to 4 pairs 
of lower pine are vestigial, but this change is abrupt, the lamina never being 
gradually long-attenuate to the base. 
The following specimens are in the U. S. National Herbarium: 
Jamaica: Mount Airy, Mazon 853. Chestervale, Underwood 3269. Near 
Cinchona, alt. 1,500 meters, Underwood 3113. Above Abbey Green, on 
trail to Blue Mountain Peak, Maron 1895, Vicinity of Hollymount, 
Mount Diabolo, alt. 750 meters, Maron 2300. Near Mandeville, alt. 600 
1 Abh. Senckenb. Ges. Frankfurt 2: 70. 1856. 
