ANSER. 115 
3.30, middle toe 2.15-2.50. Hab. Interior of North America, east of 
Rocky Mountains, breeding on the eastern shores of Hudson’s Bay ; 
migrating south, in winter, through Mississippi Valley to the Gulf 
coast; occasional on Atlantic coast. 
169.1. C. czerulescens (Linn.). Blue Goose. 
6. Plumage of adult entirely white, except primaries and their coverts; young 
grayish white, the upper parts striped with dusky grayish. 
Adult: Uniform pure white, the head often stained with rusty; pri 
maries black, becoming grayish basally, their coverts, and the 
alule, ash-gray. Young: Head, neck, and upper parts pale grayish, 
the feathers of the latter with whitish edges and (especially wing- 
coverts and tertials) striped medially with darker; rump, upper 
tail-coverts, tail, and lower parts plain white. 
ce’. Length about 23.00-28.00, wing 14.50-17.00 (16.36), culmen 1.95- 
2.30 (2.15), tarsus 2.80-3.25 (3.01), middle toe 2.00-2.50 (2.34). 
iggs 3.13 X 2.12, Hab. Western North America, breeding in 
Alaska; migrating south, in winter, to southern California and 
Gulf of Mexico; northeastern Asia. 
169. C. hyperborea (Pat.). Lesser Snow Goose. 
ce. Length about 30.00-38.00, wing 17.35-17.50 (17.42), culmen 2,55- 
2.70 (2.63), tarsus 3.15-3.50 (3.28), middle toe 2.60-2.80 (2.70). 
Hab. Eastern North America; breeding in northern Greenland, 
and probably arctic regions east of Mackenzie River; United 
States (Mississippi Valley to Atlantic coast) only during migra- 
tions and in winter. 
169a. C. hyperborea nivalis (Forsr.). Greater Snow Goose. 
a. Bill comparatively weak, the commissure not gaping, and not enclosing a dis- 
tinct blackish space; feathering at base of upper mandible, along each side, 
forming a nearly straight, oblique line ; culmen 1.70 or less. 
Adult with basal portion of upper mandible often wrinkled and warty; 
plumage, at all ages, as in C. hyperborea, but young rather lighter in 
color, with the darker stripes of upper parts less strongly contrasted ; 
length 20.00-26.00, wing 13.75-15.50, culmen 1.50-1.70, tarsus 2.30-3.00, 
middle toe 1.80-2.05. Hab. Interior of Arctic America in summer; mi- 
grating south, in winter, to southern California, and eastward to Mon- 
CAND spoics asesswsseeceasaasoccoiunt 170. C. rossii (BarrD). Ross’s Snow Goose. 
Genus ANSER Brisson. (Page 87, pl. XXVIIL., fig. 3.) 
Spectes. 
Common CHaractrrs.—Plumage brownish, the feathers of back, etc., with 
lighter tips; lower parts pale brownish gray or grayish white, becoming pure 
white on under tail-coverts ; upper tail-coverts white; tail dusky, tipped with white. 
1 References given on page 351 (“ Hypothetical List”) of the A. O. U. Check List. It is, however, beyond 
question a good species. 
