MAXON—STUDIES OF TROPICAL AMERICAN FERNS. 551 
only the original specimens being again cited. The illustration accords per- 
fectly with several Lesser Antilles specimens at hand which show this to be a 
distinct species. Of these specimens one is in the U. S. National Herbarium 
(no. 692056) ; it is from Guadeloupe, Duss ‘4084, 4085; 4086,” and came associ- 
ated under this collective number with four individuals of P. taenifolium, the 
label reading “P. trichomanoides Sw.” The other numbers, all in the Under- 
wood Herbarium of the New York Botanical Garden, are as follows: 
GUADELOUPE: Duss 4371 in part (the other element is P. taenifolium). 
Duss ‘4084, 4085, 4086” in part (mixed with P. hartii and P. taeni- 
folium). Several fragmentary specimens collected by L’Herminier 
(no. 106), presumably type material, and with them two fronds of P. 
hartii and two of P. taenifolium. 
MARTINIQUE: Duss 1654 in greater part (excellent specimens, with one 
plant of P. taenifolium). Duss 1654b (two sheets, one of which is in 
part P. hartii). 
Dominica: Laudat, Lloyd 121 in small part (the other specimens mostly 
P. hartii). Mount Diablotin, Lloyd 874. Mount Diablotin, alt. 900 
meters, Lloyd 897. 
From these specimens a complete description has been written for the North 
American Flora. Though manifestly of close alliance to P. trichomanoides, to 
which it is reduced by Hieronymus,’ P. serricula has excellent characters for 
its recognition, differing not only in the shape of its segments but also in its 
fewer sete, its less rigid, thinner, and more translucent leaf tissue (P. tricho- 
manoides having rigid, thick, herbaceous, and nearly opaque leaf tissue), and 
in its venation. In a few specimens the fertile vein branch is extended a short 
distance beyond the sorus and ends in a noticeable hydathode; but in most 
others the fertile spur of the vein is hardly visible, being in fact so short that 
the sorus is actually sessile upon the upper side of the main vein and chiefly 
overlies it, and a hydathode is usually not developed. The nongibbous, more 
or less triangular segments and the characteristic aspect of the plant alone 
ordinarily distinguish it from P. trichomanoides, however, for it agrees indif- 
ferently only with those few young or small fronds of the latter in which the 
gibbous form of the segments has not yet been developed. 
16. Polypodium basiattenuatum Jenman, Bull. Bot. Dept. Jamaica II. 4: 114. 
1897. PLATE 36, 
TYPE LOCALITY: Blue Mountains, Jamaica. 
DISTRIBUTION: Known only from the Blue Mountains of Jamaica, altitude 
1,500 to 2,220 meters. 
Following his description of this species, Jenman comments upon it as 
follows: - 
Common above 5,000 ft. altitude on the branches of trees; a much softer 
plant than any of its allies, from which it is further distinguished by its 
weaker habit, characteristically attenuated base of the fronds, the oblong 
broadly rounded, unlobed segments, lying obliquely side by side so close that 
the base of each is not expanded; the longer, softer, surface-hairs, which 
glisten in sunlight with a beautiful reddish fulvous hue, and the usually 
larger sori. Hitherto ascribed to the mainland P. truncicola Klotzsch, a‘stiffly 
erect species with deltoid segments set horizontally, like the teeth of a saw, but 
possessing the same beautiful, soft, silky vestiture. 
*Among other specimens cited by Hieronymus under P. trichomanoides are 
two from Guadeloupe, both determined by Mettenius as P. serricula, and a Brit- 
ish Guiana specimen collected by Schomburgk, which has not been seen by the 
writer. 
