PHALACROCORACID.E THE CORMORANTS. 203 



Phalacrocorax dilophus (Swains.) 



DOTJBLE-CBESTED COKMOBANT. 



Popular synonyms. Black Loon; Nigger Goose (coast of Virginia): Black Swan (Nevada). 

 Pelecanus (Carlo) dilophus Sw. & RICH. P. B.-A. ii, 1831, 473. 



Phalacrocorax dilophus NUTT. Man. ii, 1834, 483. AUD. Orn. Biog. iii,1835. 420; v. 1839, 



629, pi. 257; Synop. 1839, 302; B. Am. vi, 1844, 423, pL 416. RIDGW. Norn. N. Am, B. 



1881. No. 643; Man. N. Am. B. 1887, 78.-CouES, 2d Check List, 1882, No. 751. -B. B. 



& B. Water B. N. Am. ii, 1884, 149. A. O. U. Check List, 1886, No. 120. 



Graculus dilo hus GEAT, Gen. B. iii, 1849. BAIED, B. N. Am. 1858, 877; Cat. N. Am. B. 



1859, No. 623. COUES, Key, 1872. 303; Check List, 1873, No. 530. 

 Oraculus dilophus a. dilophus COUES, B. N. W. 1874, 587. 



HAB. Northeastern North America, breeding from northern United States northward; 

 south In winter to the Gulf coast. 



SP. CHAE. Basal outline of the gular pouch extending straight across the throat or 

 projecting slightly bauk along the median line. Adult, in full breeding plumage: Head, 

 neck, rump, and enti e lower parts, glossy black, with a faint luster of dull bluish green; 

 back, scapulars, and wings, dull grayish brown, each feather conspicuously and broadly 

 bordered with black. A tuft of narrow, 'engthened, curved feathers on each side the 

 crown, springing from behind and above the eye, these feathers either wholly black (in 

 eastern specimens), mixed black and white (in specimens from the interior), or wholly 

 pure white (in Pacific coast examples); ueck sometimes, but rarely, with a few scattered 

 white filamentous feathers. Maxilla black, mottled with grayish or dull yellowish along 

 the sides; mandible yellowish or pale bluish, mottled with dusky; loral region and gular 

 sac deep orange ; eyelids and whole interior of the mouth bright cobalt-blue, the former 

 sometimes dotted with white; iris bright grass-green; legs and feet deep black.* Adult 

 in winter: Similar to the above, but tuits of the head wanting, and the bare skin of the 

 lores, gular pouch, etc., deep yellow instead of orange, and the bluish of the mouth and 

 eyelids absent. Young, first plumage: Head and neck grayish brown, lighter next to 

 the gular sac, darker on the crown and nape ; back, scapulars, and wings, dull brownish 

 gray, the feathers bordered with dusky brown; rump dusky brown; primaries and tail 

 dull grayish black ; lower parts light fawn-color, darker on the sides, anal- region, and 

 crissum. Bill dull brownish yellow, nearly black on the culmen; gular sac deep chrome- 

 yellow; iris greenish gray ; legs and feet deep black. Young, in winter: Similar to the 

 above, but throat, chest, and breast paler, sometimes quite white. 



Total length, about 29 to 33.60 inches; extent, 45 to 55; wing, 12.00-13.00 (average 12.50) ; 

 tail, 6.50-7.80 (7.15); culmen, 2.00-2.45 (2.25). 



The Double-crested Cormorant is a transient visitor in Illinois, 

 arriving from the North in September or October and returning 

 from its winter quarters in the Gulf States and Lower Mississippi 

 Valley in March or April, according to the latitude. It doubt- 

 less occasionally remains during mild winters in the southern 

 portion of the State. 



"Like the common Black Cormorant (P. ca/rbo), this bird lives 

 entirely on fish, which it catches by pursuing them under water, 



* Audubon gives the fresh colors as follows: "Adult male, at commencement of the 

 breeding season: Upper mandiblo dusky, along the edges grayish- yellow; lower yellow, 

 irregularly marked with dusky toward the edges. Iris bright green, margin of eyelids, 

 bare space on the head, and gular sac, rich orange. Feet and claws black." 



