784 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 



FRATERCULA ARCTICA ARCTICA (Linnaeus). 



PTJFFIN. 



Adults in breeding plumage (sexes alike). — Pileum uniform deep 

 grayish brown (deep fuscous or chffitura drab) passing into light 

 brownish gray on anterior portion of forehead; rest of upper parts, 

 together with sides of neck and a broad band across foreneck uniform 

 black, the band across foreneck, however, inclining toward color of 

 pileum, the })lack of nape sharply defined against the dark grayish 

 brown of pileum; sides of head very pale brownish gray or almost 

 grayish white on loral and suborbital regions, passing into light 

 mouse gray posteriorly (including supra-auricular region) the malar 

 region mostly mouse gray passing into grayish white next to base of 

 mandible (narrowly) but posteriorly separated from the blackish 

 of neck by a space of pale brownish gray; under parts of body, 

 together with lower foreneck, immaculate white; under wing-coverts 

 light brownish gray ; bill with basal lamina of maxilla and first ridge 

 of both maxilla and mandible dull yellow, the nasal cuirass and basal 

 portion of mandible grayish blue or bluish gray, the remainder 

 vermilion red, the tip of mandible and terminal grooves yellowish; 

 rictal rosette gamboge yellow; inside of mouth, together with tongue, 

 yellow; iris light blue" or hazel brown ;^ eyelids vermilion red, the 

 callosities bluish gray or grayish blue; legs and feet vermilion red or 

 coral red.^ 



Winter plumage. — Similar to the breeding plumage except color 

 and form of basal portion of bill, color of anterior portion of sides of 

 head, and other minor details; nasal cuirass and basal lamina of bill 

 wanting and replaced by membrane of bro^N'nish black color; rictal 

 rosette much reduced and dull purplish red instead of yellow ; eyelids 

 dull purplish red and destitute of the callous appendages; whole of 

 loral and orbital regions blackish; legs and feet paler red. 



Young. — Similar to winter adults, but with bill much smaller, 

 without grooves or ridges, and much duller in color. 



Downy young. — Plain dark sooty grayish brown, paler below, the 

 breast and upper abdomen dull grayish white passing into grayish 

 laterally, or, sometimes, quite abruptly pure white. 



Adult male.— Win^, 158-168 (162.8); tail, 42-51.5 (48); culmen, 

 45-53.5 (49.8) ; greatest depth of bill, 37-42 (39.7) ; tarsus, 24-29.5 

 (26.4); middle toe, 35.5-42.5 (37.7).'^ 



a According to Audubon. 

 ^ According to Coues. 



c These are the colors of freshly killed and li^-ing specimens; in dried skins the 

 colors are, of course, very different. 

 <* Fourteen specimens. 



