400 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
its proper genus, then by Mettenius, as Polypodium serrulatum (Swartz) Mett. This 
however, is an untenable name, having been given previously by Swartz (in 1801) 
to another Jamaican fern now known as Dryopteris serrulata (Swartz) C. Chr. The 
two other specific names, orientalis and extensa, given by Desvaux and Fée, respec- 
tively, are untenable under Polypodium and a new name has thus been found 
necessary. 
No detailed description of the species is required, its marked specific characters 
having been stated repeatedly by various writers. Hieronymus! in particular 
has supplemented Mettenius’s excellent diagnosis by ample descriptive notes. All 
of these authors, however, have failed to emphasize one peculiar feature of the vena- 
tion—the upward course of the fertile veins close to the midvein before diverging 
obliquely toward the margin. The sori being basal and elongate are, therefore, borne 
against the midvein in a double and very nearly straight line, and are confluent at 
all stages of growth. If the genus Xiphopteris 
of Kaulfuss is to be recognized, it must be 
restricted to this the type species, which differs 
conspicuously from most members of ‘‘Eupoly- 
podium.’”’ But this character is only an ex- 
' treme development of a tendency noted in 
several nearly related species and seems decid- 
edly of less than generic importance. Hooker’s 
plate, cited above, is excellent. The drawing 
by House, herewith reproduced (fig. 8), shows 
better, at twice natural size, the peculiar direc- 
tion of the veins. 
A long list of specimens is given by Hierony- 
mus, many of these being of the older, historic 
collections. The following material, not cited 
by him, is in the U. S. National Herbarium: 
Jamaica: Second Breakfast Spring, alt. 600 
meters, on wet, grassy slope, Maxon 
poe 
Fig. 8.—Polypodium dualc, from Tweedside, 
Jamaica ( Mazon 906). a, Lower view of 906. Tweedside, alt. 600 meters, on 
fertile tip of lamina, showing the sori basal mossy bowlder, Mazon 980. Near 
upon the veins and thus forming a sinuous Morces Gap, alt. 1,500 meters, on bank, 
line against the costa; b, tip of a fertile Maxon 1218. Highest slopes of John 
lamina, the fertile portion subplicate, a 
common condition at maturity. Scale 2. Crow Peak, alt. 1,700 meters, on a 
mossy tree trunk, Mazon 1334. Vicinity 
of New Haven Gap, alt. 1,650 meters, on mossy branches of forest trees, 
Maxon 2686. Cuna Cuna Pass, on rocks, Fredholm 3226. Morces Gap, Harris 
7136; Clute 45. Northwest slopes of Dolphin Head, alt. 420 meters, Harris 
9282. Near Cinchona, alt. 1,500 meters, on banks, Underwood. Without 
locality, Hart 102. 
CusBa: Without definite locality, Wright 780. 
Hayri: Le Brande to Mount Balance, alt. 1,065 meters, on rocks, Nash 4 
Taylor 1720. 
Porto Rico: Eastern slope of the Luquillo Mountains, alt. 450 meters, Heller 
4620. Luquillo Mountains, P. Wilson 30, 69, 176. ‘‘Sierra de Naguabo,”’ 
in arboribus vetustis sylvae montis ‘‘ Piedra Belleta,’’ Sintenis 1000. Mount 
Torresilla, Hioram 291. 
St. Krrrs: Slopes of Mount Misery, on trees, Britton & Cowell 500. 
Grenapa: ‘‘Morne au Camp,’? among mosses on trees, Eggers 6216. Without 
locality, Sherring 139. 
Sr. Vincent: Souffriére, alt. 720 meters, among mosses on trees, Eggers 6709. 
1 Hedwigia 44: 80-83. 1905. 
