60 ALCIDjE. — OOLTMBIDJE. 



Arctic, 352. Thick-billed or BEtJNNiCH's Guillemot. Uria hruennichi, E. 



Sabine. Hecorded on somewhat slight evideuce. 



Larger and darker than last, and with shorter and stouter bill, base of 

 the upper mandible wdiitish. 



353. Black Guillemot. Uria gryJle (Linnaeus). Eesident : breeds 

 on Isle of Man, Scotch and Irish coasts. 



Legs, feet, and inside of mouth vermilion. 



In summer. Black, middle and great wing-coverts, basal half of inner 

 web of primaries, under wing-coverts, and axillaries white ; wing-coverts 

 with hidden black bases. 



In ivinter. Head and nape white, speckled with black ; back, scapulars, 

 and upper tail-coverts black, barred with white ; rump and underparts 

 white ; wings and tail black ; bill black, red at base. Length 14 inches, 



Arctic. 354. Little Auk. Mergulus alle (Linnaeus). In winter. 



Bill black, shorter than head, thick, broader than high at base. 



In summer. Above black, except ends of secondaries and sides of 

 scapulars, wliich are margined with white : small white spot over eye ; 

 chin, throat, and fore neck black ; rest below white. 



In ivinter. The same ; but chin, throat, and fore neck are white. 

 Length 8| inches. 



355. Puffin. Fratercula arctica (Linnaeus). Eesident. 



Bill shorter than head, higher than long ; both mandibles arched 

 (and in summer grooved across with orange). 



Above black ; forehead and crown greyish brown ; black ring round 

 white throat ; below white ; axillaries bro\\"n ; legs orange. 



In ivinter the bill is smaller and without brighter colour, the base of 

 the bill being shed in autumn. Length 12 inches. 



COLYMBID^. 



(Females smaller than males.) 



356. Great Northeriv Divee. Cohjmhus glacialis, Linnaeus. Chiefly 

 autumn to spring ; occurs in the Shetlands in summer. 



Adult : spring. Head and neck black, with purple gloss ; a band of 

 white stripes on throat, below which is another band of white stripes ; 

 bill black ; iris red. 



Winter. Above uniform blackish bro\^n, more or less spotted with 

 white; below white. Length 30-33 inches. 



Arctic. 357. White-billed Northern Diver. Colymbus adamsi, G. R. 



Gray. Scarce or overlooked straggler. 



Besembles Great Northern Diver, but is larger. Adults have yellowish- 

 white bill, upper mandible shghtly curved up, and the white spots on 

 back larger. 



