436 
LAMELLIROSTRAL SWIMMERS — ANSERES. 
it by Mr. D. G. Elliot, since the difference in the character of the bill from that of the typical 
species of the genus is hardly of generic value. The species may be distinguished as follows : — 
Synopsis of Species. 
A. Plumage never chiefly white ; the adult mainly grayish brown, with bluish-gray rump and 
wing-coverts, the head and part of the neck white. Young almost wholly grayish brown, 
including head and neck. 
1. C. Ccerulescens. Bill very robust, the posterior lateral outline of the maxilla decidedly 
concave ; commissure widely gaping, and lower outline of the mandible decidedly convex. 
Wing, about 15.00-17.00 inches; culmen, 2.10-2.30 ; tarsus, 3.00-3.30 ; middle toe, 2.15 
-2.50. Hah. Interior of North America ; Mississippi Yalley, chiefly in winter. 
B. Plumage of the adult pure white, the primaries black, more grayish toward the base ; young 
grayish white, the centres of the feathers darker gray. 
2. C. hyperboreus. Bill robust, and shaped like that of G. ccerulescens. Wing, 15.00-18.50 
inches ; culmen, 1.95-2.80 ; depth of maxilla at base, 1.15-1.50 ; tarsus, 2.80-3.50 ; 
middle toe, 2.10-2.90. Hob. The whole of North America. 
3. C. Rossi. Bill small, the posterior lateral outline of the maxilla almost perfectly straight, 
the tomia closely approximated, and the lower outline of the mandible scarcely convex ; 
in older specimens the base of the maxilla corrugated or warty. Wing, 13.75-15.50 
inches ; culmen, 1.50-1.70 ; depth of maxilla at base, .85-. 95 ; tarsus, 2.30-3.00 ; middle 
toe, 1.80-2.05. Hab. Northwestern North America. 
Chen Ccerulescens. 
THE BLUE-WINGED GOOSE. 
Anas ccerulescens, Linn. S. N. ed. 10, I. 1758, 124; ed. 12, I. 1766, 198. — Gmel. S. N. I. 1788, 
513. — Lath. Ind. Orn. II. 1790, 836. 
Anser ccerulescens, Vieill. Enc. Meth. I. 1823, 115. — Baird, Cat. N. Am. B. 1859, no. 564. — 
Coues, Key, 1872, 282 ; Check List, 1873, no. 479 ; Birds N. W. 1874, 553. 
Chen ccerulescens, Ridgw. Proc. U. S. Nat. Mus. Vol. 3, 1880, 202 ; Norn. N. Am. B. 1881, no. 
590. — Coues, Check List, 2d ed. 1882, no. 694. 
Anser hyperboreus (supposed young), Stephens, Shaw’s Gen. Zool. XII. ii. 1824, 33 . —Baird, 
B. N. Am. 1858, 760. 
Hab. North America in general, but chiefly the interior. 
Sp. Char. Adult: Head and upper half of the neck white, or mostly white, the former fre- 
quently washed with orange-rufous anteriorly ; lower neck and body grayish brown, the feathers 
bordered terminally with paler, these pale edgings, however, nearly obsolete on the neck, where 
the tint is darker, inclining to plumbeous-umber, which joins irregularly against the white above 
it. Rump and wings plain pearl-gray or bluish cinereous (the former sometimes white), in strik- 
ing contrast to the deep grayish brown of the scapulars, sides, etc. ; that of the rump fading into 
white on the upper tail-coverts, and that of the greater coverts edged externally with the same. 
Primaries black, fading basally into hoarjr gray ; secondaries deep black, narrowly skirted with 
white ; tail deep cinereous, the feathers distinctly bordered with white. Bill reddish, the com- 
missural space black ; feet reddish. Young : Yery similar, but the chin, only, white, the rest of 
the head and neck being uniform plumbeous-umber or brownish plumbeous, like the breast, only 
darker in shade ; body more cinereous than in the adult, the pale tips to the nearly truncated 
contour-feathers being obsolete. Rump, wings, and tail as in the adult. Bill and feet blackish. 
Downy young, not seen. 
Total length, about 30.00 inches ; wing, 15.00-17.00 ; culmen, 2.10-2.30 ; tarsus, 3.00-3.30 ; 
middle toe, 2.15-2.50. 
The chief variation in the plumage of adults of this species consists in the extent and continuity 
of the white of the neck. This is usually more or less broken, the dusky of the lower portion 
running upwards in irregular spots or projections ; it extends highest on the nape, where it some- 
