MAXON—STUDIES OF TROPICAL AMERICAN FERNS. 5738 
very broad, and the fertile fronds long-stipitate, the lamina linear-oblong and 
nearly or quite pinnatisect, the pinnules often distant. 
The following specimens in the U. 8. National Herbarium are grouped ten- 
tatively under P. leucosticton: : 
GUATEMALA: Pansamalé, Dept. Alta Verapaz, alt. 1,150 meters, von Tiirck- 
heim (J. DB. Smith, no. 643). Same locality, J. D. Smith 1572. Cobén, 
Alta Verapaz, alt. 1,850 meters, von Tiirekheim II. 1397; II. 2487. 
Costa Rica: Vicinity of La Palma, alt. 1,450 to 1,550 meters, on tree 
trunks at edge of forest, Maron 449 (type locality of P. plebejum 
palmense Christ). 
CoLoMBIA: Dense forests near Popoyin, alt. 1,750 meters, Lehmann 3556. 
Same general region, alt. 1,600 to 2,000 meters, Lehmann 5724. 
VENEZUELA: Los Tegfies, alt. 1,150 meters, Hggers 13041. 
Ecuapor: Mount Tunguragua, alt. 1,600 to 2,300 meters, Lehmann 460. 
17. Polypodium plebejum Schlecht. & Cham. Linnaea 5: 607. 1830. 
Polypodium karwinskyanum A.Br.; Mett. Abh. Senckenb. Ges, Frankfurt 2: 
66. 1856, in part. 
Polypodium cheilostictum Fée, Mém. Foug. 8: 87. 1857. 
Polypodium plebeium cooperi Baker, Journ. Bot. Brit. & For. 25: 25. 1887. 
TYPE LOCALITY: Jalapa, Mexico (Schiede 746). 
DistrisuTion: Eastern central Mexico to western Panama, ascending to 
2,400 meters in Panama, but occurring mainly at lower altitudes. 
The type collection of P. plebejum, from Jalapa, which is in the humid region 
of the eastern part of southern Mexico, has not been seen by the writer; but 
from this general region and the area southward of Costa Rica there is at 
hand a wealth of material which seems to place the identity of this species 
beyond question. These specimens include several collections so determined 
by Hieronymus and the whole range of North American specimens cited below 
doubtless pertains to a single species. The South American material pre- 
viously so referred must probably all be excluded, the wide distribution 
hitherto ascribed to the species having been due mainly to a lack of critical 
study. 
Both in size and shape of the fronds and segments P. plebejum varies 
widely. The largest plants seen (Pringle 3258) have the fronds about 50 cm. 
long, the stipe and lamina being about equal in length. The rhizome is stout 
and ropelike, very thickly covered with short, very closely packed, brownish, 
crispate, divergent but scarcely projecting scales; and, since it is mostly 
epigean, these are conspicuous, especially in the long-produced apical portion 
which commonly extends beyond the fronds a distance of 3 to 10 centimeters. 
This is in sharp contrast to P. guttatum, The scales of the under side of the 
lamina are the best specific mark; they are usually very few and minute, 0.5 
to about 1 mm. long, deltoid-lanceolate or nearly linear frrm a short triangular 
base, the margins subentire to irregularly and for tie most part bluntly 
bidenticulate, never having the long, slender, almvst cilia-like teeth of 
P. oulolepis. In all of the specimens here listed tr sori are distinctly im- 
pressed at maturity. 
Polypodium cheilostictum Fée, described upon specimens collected at Orizaba 
by W. Schaffner (no. 548) in 1856, is probably synonymous with P. plebejum, 
though listed by Fournier as distinct. The type locality is not far from that 
of P. plebejum and the description indicates no points of difference. 
Polypodium karwinskyanum A. Br., which was first definitely described by 
Mettenius, seems to be mainly this species, although according to Kuhn and 
