347 
877. 
818 SYSTEMATIC SYNOPSIS.— PYGOPODES. 
this bare turgid space flesh-colored in life, drying pale yellowish. Length 18.00; extent 32.00; 
wing 8.50; tarsus 1.25; bill along culmen 1.40, along gape 2.20; gonys 0.90; depth at angle 
0.55, width at base of nostrils 0.30, at angle of mouth 0.80. N. Atlantic and Polar and 
N. Pacifie shores and islands, in myriads; on the Atlantic S. in winter to the Middle States, 
breeding from the Gulf of St. Lawrence northward. The N. Pacific form, unquestionably 
of the ‘ thick-billed” species, does not exhibit the extreme of shortness and stoutness as just 
described for the At 
lantic; with a ecul- 
men of about 1.67, 
the depth opposite 
nostrils is hardly 0.67, 
thus less than half 
the length of culmen, 
instead of about half; 
gape nearly 3.00. 
The sides of the up- 
per mandible are char- 
acteristically dilated 
and denuded, of a 
glaucous bluish color; the tip of the bill is less deflexed, though more so than in the common 
guillemot. This is the great ‘‘egg-bird” of the high N. Pacific; on St. George’s, one of th 
Prybilov group, for example, the birds ‘‘go flying around the island in great files and platoons, 
always circling against or quartering, on the wing, at regular hours in the morning and the 
evening, making a dark girdle of birds more than a quarter of a mile broad and thirty miles 
long, whirling round and round the island, and forcing upon the most casual observer a lasting 
impression.” The N. Pacific form is L. arra proper; that of the N. Atlantic is ‘‘ Briimnich’s 
guillemot,” differing as said, and perhaps constituting a subspecies apart (L. a. svarbag). 
UTAMA/NIA. (Cretan name of the bird.) Razor-BitL AuK. Size, form, and general 
aspect of the last genus. Bill about as long as 
head, densely feathered for half its length, the ’ 
feathers extending on upper mandible beyond mid- 
dle of commissure, those on lower somewhat far- 
ther. Bill greatly compressed, cultrate, suleate, 
hooked; culmen ridged, regularly convex; com- a 
missure straight to the hook; gonys about straight. 
Nostrils linear, marginal, densely feathered. Tarsi 
seutellate in front. Tail short, pointed, of stiffish, 
acute feathers. Wings normal, effective for flight. Fie. 559. — Thick-billed Guillemot, nat, size. 
Bicolor. Egg single, colored. One species. ; 
U. tor’da. (Name of the bird.). Razor-sintep AUK. TINKER. Adult in summer: Bit! 
and feet black, the former with a white line occupying the length of the middle sulcus on both 
mandibles; mouth yellow; eye bluish. A strict, sunken line of white from eye to base o. 
culmen. Head and neck all.around and‘ upper parts black, glossy and intense on the latter 
lustreless opayue brownish-black on the sides and front of the former. Tips of secondaries 
and entire under parts from the neck, including lining of wings, white. In winter: White 
reaching to bill, and invading sides of head and neck ; the dark parts duller. Young: Like 
the adults in winter; smaller; duller; bill unformed, and like the feet not black. Nestlings 
clothed with sooty down, paler or whitish below. In the adults, the sharp white line from 
bill to eye is very characteristic, appearing with the first feathering, but sometimes fails in 
winter birds. Length about 18.00; extent 27.00; wing 7.75; tail 3.50, graduated 1.25; 
Fig. 558. — Californian Guillemot, nat, size. 
