130 BIRDS OF ILLINOIS. 



Anas obscura Gmel. 



DUSKY DUCK. 



Popular synonyms. Black Mallard; Black Duck; Black English Duck (Florida). 



Anas obscura GMEL. S. N. i, pt. ii, 1788, 541. WILS. Am.Orn.viii,1814,141,pl.72,flg.5. NUTT 

 Man. ii, 1834, 392. AUD. Orn. Biog. iv, 1838, 15, pi. 302; Synop. 1839,276; B. Am. vi, 1843, 

 244,pl. 386. BAIKD, B. N. Am. 1858, 775; Cat. N. Am. B. 1859, No. 577. COUES, Key. 1872, 

 285; Check List, 1873, No. 489; 2d ed. 1882, No. 708; B. N. W. 1874, 560.-EiDGW. Nom. N. 

 Am. B. 1881, No. 602; Man. N. Am. B. 1887,. 91. B. B. & R. Water B. N. Am. i, 1884, 499. 

 -A. 0. U. Check List, 1886, No. 133. 



HAB. Eastern North Amei-ica, west to the Mississippi Valley, north to Labrador and 

 Fort Anderson and York Factory; breeding from Long Island, northern Illinois, and Iowa, 

 northward. 



SP. CHAE. Adult. Prevailing color brownish black or dusky, the feathers edged, more 

 or less distinctly, with pale grayish fulvous. Head and neck about equally streaked with 

 grayish white (more ochraceous near the bill) and dusky; pileum nearly uniform dusky, and 

 a dusky stripe back from the eye. Speculum violet, changing to green in some lights, 

 narrowly tipped with white, and with a broad subterminal bar of velvety black ; last row of 

 coverts dusky brownish, broadly tipped with black. Sexes alike. "Bill yellowish green, 

 the unguis dusky; iris dark brown; feet orange-red, the webs dusky" (AUDUBON). 



Wing, 10.50-11.50 inches; culmen, 2.00-2.35; tarsus, 1.70-1.80; middle toe, 1.90-2.10. 



Downy young. Above oiivaeeous-brown, faintly relieved by six inconspicuous mark- 

 ings of light brownish buff, situated as follows: one on the posterior border of each arm- 

 wing; one (small and sometimes nearly obsolete) on each side of the back, behind the 

 wings, and one, more distinct, on each side the rump, near the base of the tail. Pileum and 

 hind neck (longitudinally) brown, like the back; rest of the head and neck, with lower parts, 

 light dingy brownish buff, paler on the abdomen; side of head marked with a narrow dusky 

 stripe running from the upper basal angle of the maxilla to the eye, thence back toward the 

 occiput, but scarcely confluent with the brown on the latter; an indistinct spot on the 

 auricular region, with a still less distinct dusky mark extending back from this to the nape. 



A summer specimen from Moose Factory, Hudson's Bay Territory (No. 17,971, JOHN Mc- 

 KENZIE), differs from fall, winter, and spring examples from the United States in having: 

 the pale edges of the feathers nearly all worn off, so that the plumage appears to be almost 

 uniform black, while the lower parts are strongly tinged with rusty, this approaching a 

 bright ferruginous tint on the breast. Some examples have a slight tinge of metallic green 

 on the sides of the head, behind the eye. 



The Dusky Duck is chiefly an eastern species, and reaches 

 nearly the western limit of its range in Illinois. Just how far 

 to the west and southwest it extends is unknown, but Col. N. 

 S. Goss is convinced that it does not Occur in Kansas, where a 

 quite distinct though a somewhat similar species, Anas fulwigula, 

 iiiKculosa (Senn.), replaces it. It has been recorded from Utah 

 Lake, Utah, but in view of what we now know the record in 

 question doubtless refers to the species just mentioned. 



Professor Cooke says that "though principally a bird of the 

 Eastern States, the Black Duck is not rare in the northern part 

 of the Mississippi Valley," and that it breeds in Iowa and Illi- 

 nois, but he does not give particulars as to its breeding in the 

 latter State. 



