BIRDS-AN ATINAE—DAFILA. 
775 
List of specimens. 
Catal. 
No. 
Sex. 
Locality. 
When col¬ 
lected. 
Whence obtained. 
Orig’l 
No. 
Collected by— 
Length. 
Stretch 
of wings. 
Wing. 
872 
873 
6897 
6891 
9691 
9699 
9696 
5887 
9693 
9697 
9701 
9698 
9692 
3 
9 
3 
9 ° 
3 
3 
3 
Nov. 25, 1842 
S. F. Baird. 
22 75 
22,25 
37.00 
36.50 
11.00 
11.00 
Upper Mississippi and Yellowstone 
Mar. —, 1855 
Feb. —, 1855 
July 6,1853 
30 
3 
Presidio, (near San Francisco) .. 
3 
21 
31 
Feb. 2, 1854 
24.00 
37.00 
11.50 
ANAS OBSCURA, Gm. 
Black Duck; Dusky Duck. 
Anas obscura, Gm. Syst. Nat. I, 1788, 541. — Lath. Ind. II, 1790.— Wilson, Am. Orn. VIII, 1814, 141 ; pi. Ixxii, 
f. 5.— Ib. Ord’s ed. VIII, 155.— Bon. Obs. Wils. 1825, 260.— Ib. Syn. 234. — 4ud. Orn. Biog. IV, 
1838, 15; pi. 302. —Ib. Syn. 276. —Ib. Birds Araer. VI, 1843, 244; pi. 386. —Eyton Mon. Anat. 
1838, 140. 
Anas ( Boschas ) obscura, Nuttall, Man. II, 1834, 392. 
Dusky Duck. —Pennant, Arc. Zool. IT, 564. —Lath. Ill, ii, 545. 
Sp. Ch. —Bill greenish ; feet red. Body generally blackish brown; the feathers obscurely margined with reddisli brown; 
those anteriorly with a concealed V-shaped mark, more or less visible on the sides of the breast. Head and neck brownish 
yellow, spotted with black ; the top of head and nape dark brown, with a green gloss on the sides behind. Wings dull blackish, 
with a dull greenish gloss. Speculum violet, terminated with black. Inner tertials hoary gray towards tip. Axillars and 
inside of wing white. Tail of 18 feathers. 
Female similar, but rather duller ; the light edges to the under feathers more conspicuous ; the sides of head without the 
greenish gloss. The speculum bluish, with less violet. 
Length of male, 22 inches ; wing nearly 12 ; tarsus, 1.80 ; commissure, 2.56. 
Hab. —Atlantic region of North America. Not yet detected on the Pacific, nor in Europe. 
This is the most plainly marked as well as, perhaps, the largest of our river ducks, and 
excelled by none in the excellence of its flesh. 
List of specimens. 
Catal. No. 
Sex. 
Locality. 
When collected. 
Whence obtained. 
Length. 
Stretch 
of wings. 
Wing. 
231 
Carlisle, Penn__ 
March 10, 1840-. 
S. F. Baird . 
847 
9 
.do... 
November 4, 1842.... 
_do_-_ 
22. 00 
36. 25 
10. 50 
DAFILA, Leach. 
Dafila, “Leach,” Stephens, Shaw’s Gen. Zool. XII, 1824, 126. Type Anas acuta. 
Phasianurus, Wagler, Isis, 1832. 
Ch.— Bill long, narrow ; considerably longer than the foot ; nearly linear, but widening a little to the end, which is truncate, 
rounded. Nail small. Nostrils small, in the basal third of bill. Tail pointed ; the two middle feathers lengthened, so as 
nearly to equal the wings. 
