vaca NV ATOR. 7 
Gznus URINATOR Covizr. (Page 6, pl. II, fig. 1.) 
Species. 
Common Cuaracters.—Above blackish or slaty, beneath white. Jn summer, 
upper parts spotted or speckled with white, the throat and fore-neck blackish or 
chestnut. Jn winter, and in young, upper parts without white markings, and throat 
and fore-neck white like rest of lower parts. Downy young uniform sooty grayish, 
the belly white. Mest built on ground at edge of marsh or lake. Eggs 2, elongate- 
ovate, deep brown or olive, rather sparsely speckled or spotted with dark brown 
and blackish. 
a’. Tarsus shorter than inner toe with claw; fore-neck blackish in summer. 
b. Distance from base of culmen to anterior point of loral feathers, above 
nostrils, greater than the distance from the latter point to anterior bor- 
der of nostrils. Summer plumage with head and neck black all round, 
the middle of the fore-neck and sides of lower neck each crossed by a 
bar or transverse series of white streaks. 
c', Basal depth of bill* not less than one-third exposed culmen; bill in adult 
blackish (almost wholly deep black in summer); head and neck 
glossed with velvety green ; white spots on scapulars broad as long; 
length 28.00-36.00; wing 13.00-15.25 (14.06); culmen 2.75-3.50 
(3.07); depth of bill through base .90-1.05 (.96). Eggs 3.52 x 
2.27... Hab. Northern part of northern hemisphere, breeding from 
northern United States northward..... 7. U. imber (Gunn). Loon. 
c’. Basal depth of bill less than one-third exposed culmen; bill in adult 
whitish (almost wholly yellowish white in summer); head and 
neck glossed with velvety violet-blue ; white spots on scapulars de- 
cidedly longer than broad; length about 35.00-38.00; wing 14.85- 
15.45 (15.11); culmen 3.50-3.65 (3.59) ; depth of bill through base 
1.00-1.20 (1.09). Hab. Western Arctic America and northeastern 
ARID: sec cusseseruceresste 8. U. adamsii (Gray). Yellow-billed Loon. 
b*. Distance from base of culmen to anterior point of loral feathers, not greater 
than distance from the latter point to anterior extremity of nostril. 
Summer plumage with upper part of head and hind part of neck gray- 
ish; throat and fore-neck black, without white streaks, but several lon- 
gitudinal series of the latter down the side of the neck, between the 
black and the gray. 
c'. Fore-neck and under side of neck glossed with velvety purple; occi- 
put and hind-neck deep gray, almost plumbeous. Length 26.00- 
29.00; wing 12.15-13.20 (12.55); culmen 2.50-2.85 (2.60); depth of 
bill at base, .75-.80 (.78). Hggs 3.09 1.96. Hab. Northern por- 
tions of northern hemisphere, breeding in Arctic regions; in North 
America, south, in winter, to extreme northern United States, east 
of the Rocky Mountains. : 
9. U. arcticus (Linn.). Black-throated Loon. 
1 At base of exposed culmen. 
