142 U. S, P. E. E, EXP. AND SUEVEYS — ZOOLOGY — GENEEAL EEPOET. 
List of specimens. 
Oatal. No. 
Locality. 
When col- 
lected. 
Whence ob- 
tained. 
6 
Collected by— 
Length. | 
Wing. | 
Tail. 
Tarsus. | 
Middle loe. 1 
5 
| Bill alone. 1 
| Along gape. J 
Specimen 
measured. 
Remarks. 
6017 
6018 
a 
Camp 123, Bill Williams' 
river, N. M. 
New Mexico 
Feb. 16, 1854 
Lt. Whipple.... 
Lt J. G. Parke. 
Kennerly and 
Mollhausen. 
Dr. Heermann . 
5.50 
5.25 
5.50 
Fresh . 
Eyes black. 
2.70 
0.40 
0.58 
0.28 
0.24 
0.65 
NEPHOCAETES, Baird. 
Ch. — Tail rather less than half the wings ; quite deeply forked ; the feathers obtusely acuminate ; the shafts scarcely stiffened . 
First quill longest. Tarsi and toes completely bare, and covered with naked skin, without distinct indications of scutellae. 
Tarsus rather longer than middle toe ; the three anterior toes about equal, with moderately stout claws. Claw of middle toe 
much shorter than its digit. Hind toe not versatile, but truly posterior and opposite, with its claw, rather longer than the 
middle toe without it. Toes all slender ; claws moderate. Nostrils widely ovate, the feathers margining its entire lower edge. 
This genus is widely different from Cypselus in the slender and elongated toes and tarsi, 
which are completely bare of feathers. The hind toe is elongated and usually posterior, as in 
the Oscines, instead of being directed forward and by the side of the others. The tail feathers 
are less deeply forked, the lateral being much less lanceolate and elongated. The bill is more 
decurved. The anterior toes probably have 3, 4, 5 joints, as in most birds. 
The affinities of this genus to Chaetura, as restricted, are very close, the feet being very 
similar. The shafts of the tail feathers, however, are only a little stiffened, and not mucronate. 
The tail also is deeply forked ; not even nor rounded. The larger Acanthyli of the older authors 
are still more like the present species in generic peculiarities. The tail, however, though some- 
times forked, has the feathers more or less mucronate ; the legs stouter. The genus Pallene, 
in which they have been placed, is pre-occupied according to Gray. Cypselus senex of Tem- 
minck, from Brazil, is very closely allied, the tail feathers not being mucronate. The tail is, 
however, even or slightly rounded, instead of forked. A genus Pallenis established for this 
species by Keichenbach might, without much violence, be made to include N. niger; but as this 
name is pre-occupied for another genus, there seems nothing left but to establish a new one. 
The genus Macropteryx of Swainson has naked feet, but the tarsi are excessively short and 
thick ; much shorter than any of the toes, even without the claws. The lower part of the 
tibia is partly denuded. The tail is very deeply forked, the outer feather having almost the 
extension of Hirundo rufa, and extending beyond the tips of the wings. It probably belongs 
to the section of Cypselidae with three joints to each of the anterior toes. 
NEPHOCAETES NIGER, Baird. 
Northern Swift. 
? Hirundo nigra, Gmelin, Syst. Nat. I, 1788, 1025. 
Cypselus niger, Gosse, Birds Jamaica, 1847, 63. — Ib. Illustrati s Birds Jamaica. — Gundlach and Lawrence, 
Annals New York Lyceum, VI, 1858, 268. 
Cypselus borealis, Kennerly, Pr. Ac. Nat. Sc. Phila. IX, Nov. 1857, 202. 
Hirundo apus dominicensis , Brisson., II, 17G0, 514 ; pi. xlvi, fig. 3. 
Sp. Ch. — Wing the length of the body. General color rather lustrous dark sooty brown, with a greenish gloss, becoming 
a very little lighter from the breast anteriorly below, but rather mere so on the neck and head above. The feathers on the top 
of the head edged with light gray, which forms a continuous wash on each side the forehead anterior to the usual black cres- 
cent in front of the eye. Some feathers of the under parts behind narrowly edged with gray. Bill and feet black. Length 
6.75 ; wing 6.75 ; tai; 3.00 ; depth of fork .45. 
Hub. — Northwestern America to West India islands. 
