BIEDS OF NORTH AND MIDDLE AMERICA. 681 



toe largest; anterior toes fully webbed, the anterior margin of web 

 not at all incised. 



Plum/ige and coloration.— Tlumnge in general full and blended, the 

 feathers of neck, however, hair-like, though full and dense, and those 

 of occiput and nape somewhat elongated. Coloration extremely 

 variable, sometimes entirely dusky, but usually dusky above and 

 with more or less white on under parts, the posterolateral portions 

 of neck yellowish. 



Range. — Circumpolar regions, southward in winter as far as Peru, 

 Africa, Australia, etc. (Monotypic.) 



COPROTHERES POMARINUS (Temminck). 



POMARINE JAEGER. 



Adults, liglit-colored j^Tiose (sexes alike). — Pileum, lores, and malar 

 region, together with upper parts, except nape and hindneck, plain 

 dark sooty gray; anal region and under tail-coverts lighter brownish 

 gray, sometimes intermixed with whitish; rest of head and neck, 

 including hindneck, together with under parts of body, immaculate 

 white, the auricular region and sides of nape more or less strongly 

 tinged with straw yellow; bill dull brownish (whitish in life), its 

 terminal third (approximately) black; iris dark brown; legs and 

 feet blackish, the upper portion of tarsus pale bluish (in life). 



Adults, intermediate phase (sexes alike). — Similar to the light- 

 colored phase but chest and hindneck barred or transversely spotted 

 with dusky, and lateral under parts irregularly barred with the 

 same." 



Adults, dushy pliase_ (sexes alike). — Entirely plain dark sooty gray- 

 ish brown, with a slaty cast in certain lights, the auricular region 

 sometimes (usually?) tinged with yellowish. 



Young, liglit-colored phase. — Head, neck, and under parts dull 

 buff, everywhere barred with dusky, the bars broad and sharply 

 defined on under tail-coverts and flanks, indistinct on head and neck; 

 upper parts dusky grayish brown, the scapulars and interscapulars 

 tipped with buff, the rump and upper tail-coverts spotted with the 

 same. 



Young, duslcy phase. — Entirely sooty grayish brown, the breast, 

 abdomen, and sides narrowly and rather indistinctly, the mider and 

 upper tail-coverts broadly and sharply barred with buff. 



Downy young. — Immaculate grayish brown (between benzo brown 

 and deep brownish drab) passing into paler (between benzo brown 

 and drab) on chin and under parts of body; bill brownish, the legs 

 and feet much paler brownish. 



o The majority of specimens are of this intermediate phase, the two extremes being 

 comparatively rare. A large S3ries shows every gradation between the two extremes. 



