MAXON—STUDIES OF TROPICAL AMERICAN FERNS. 567 
9. Polypodium fallacissimum Maxon, sp. nov. 
Rhizomes short-creeping, sparingly branched, the branches 1 to 8 ecm. long, 
about 1.5 mm. thick, woody, the older portions with numerous short rounded 
phyllopodia (1 to 8 mm, apart), the growing portion conspicuously paleaceous, 
the scales subappressed, imbricate, rigid, 1 to 1.5 mm. long, deltoid-ovate, long- 
acuminate, attached above their base, with a sharply defined black median line 
of strongly sclerotic cells extending from the apex to each side of the point of 
attachment (thus narrowly A-shaped), the margins composed of pale translu- 
cent cells, the outermost row transversely linear, arranged as an irregular 
papillate-denticulate border. Fronds erect or ascending, closely distichous (ap- 
pearing subfasciculate), simple or pinnately parted, the smaller simple ones 
often fertile, 2 to 3 cm. long, subspatulate, the lamina 1 to 1.5 cm. long, rounded- 
oblanceolate (the short stipe narrowly marginate), with 6 to 9 pairs of very 
oblique 1 to 38-forked veins, the sori medial, terminal upon the proximal 
branches; characteristic pinnately parted fronds 3 to 13 cm, long; stipe 1.5 to 
7 cm. long, slender, stramineous, greenish-marginate or at the apex distinctly 
alate, deciduously paleaceous; lamina 2 to 6 cm. long, 1.3 to 2 cm. broad, vari- 
able in shape, with 1 to 3 pairs of oblique, subdistant, oblong to linear-oblong, 
rounded or sharply acute, subentire to serrulate lateral segments and a similar 
or larger and elongate terminal segment, these connected by a conspicuous 
costal wing about 2 mm. broad upon each side of the low, partially concealed, 
olivaceous costa; veins close, slender, concealed, very oblique, about 7 pairs in 
the larger segments, free or very rarely subgoniophlebioid, once or twice forked, 
the large sori (5 or 6 pairs) terminal upon the first (proximal) branches, medial, 
impressed. Leaf tissue rigidly coriaceous, bright or yellowish green, smooth 
above, beneath rather densely paleaceous, the scales mostly persistent, 1.5 to 
1.8 mm. long, oblong-ovate or mostly ovate-deltoid, brownish castaneous in 
mass, subappressed, imbricate, nearly homogeneous, the cells mostly short and 
subhexagonal (the partition walls somewhat sclerotic but yellowish brown, not 
fuscous), the outer 1 or 2 rows quadrate or transversely oblong, forming an 
irregular denticulate border, the teeth entire. 
Type in the U. 8S. National Herbarium, no. 471295, collected at San Lorenzo 
Canyon, 6 miles southeast of Saltillo, State of Coahuila, Mexico, September 21 
to 23, 1904, by Dr. Edward Palmer (no. 426). The small, simple-fronded state 
of this species is represented also by Doctor Palmer’s no. 425, collected at the 
same time and place. 
Polypodium fallacissimum, though related to P. subvestitum, is readily recog- 
nized as distinct by the key characters. The scales of the under surface are 
brighter colored and rather narrower than those of P. subvestitum, their mar- 
gins also less deeply denticulate, the teeth entire rather than bipapillate. The 
last character immediately separates both P. fallacissimum and P. subvestitum 
from P. zrantholepis, a species with more slender, deeply lacerate-fimbriate 
lamina scales, their teeth very deeply bifid. 
As mentioned under P. pycnocarpum, Fournier reported as P. macrocarpum 
two collections from Jalapa, Mexico, which probably pertain to P. fallacissi- 
mum. Fée also described, as Heteroneuron paradorum, a plant collected by 
Galeotti which is either P. fallacissimum or a-very closely related form. That 
it is probably not identical with P. fallacissimum may be inferred from the 
regular goniophlebioid venation shown in Fée’s figure, but it is strikingly similar 
in habit and general appearance. Fournier? clearly is wrong in citing it as a 
*Mém., Foug. 6: 3. pl. 1. f. 4. 1853. 
7 Mex. Pl. Crypt. 84. 1872. 
