16 AORTH AMERICAN BIRDS. 



Genus CEPPHUS Pallas. (Page 9, pi. II., fig. 3.) 



Species. 



Common Characters. — Summer adults uniform l)lack, with or without white 

 on wing.s. Winter specimens white, varied above (sometimes below also) with black, 

 the wings and tail as in summer. Youvg similar to winter adults, but white of 

 wings varied with dusky, the quills marked at tips with white. Bill black ; feet 

 bright red in summer, pinkish in winter. Eijg vaiying from ovato to elongate- 

 ovate, greenish white or buffy white, heavily spotted or otherwise conspicuously 

 marked with dai'k brown and lavender-gray. 



a}. A largo white patch on outer surface of wing. 

 6'. Under wing-coverts pure white. 



c'. Greater wing-coverts white to the extreme base, sometimes a little 

 dusky along the basal portion of the shafts. Adult in summer : Uni- 

 form blackish, except a large roundish or oval patch of pure white 

 on the wing, including the greater, middle, and posterior lesser 

 coverts, these feathers all white to the base; axillars, under wing- 

 coverts, and basal half, or more, of inner webs of quills, pure white. 

 Winter plumatje : Wings as in summer; rest of the plumage pure 

 white, the upper parts varied with black. Young : Similar to winter 

 plumage, but white wing-patch broken by blackish tips to all the 

 feathers; secondaries and primary coverts marked with white at 

 ends, and lower parts indistinctly barred with dusky. Downy young : 

 Uniform sooty blackish, paler and more grayish below. Length 

 about 12.50-13.50, wing G.25-7.20, culmen 1.00-1.20, gonys .50, depth 

 of bill at nostril .35-.40. Egg 2.38 X 1-36. Hab. Circumpolar sea- 

 coasts, south in North America, in winter, to New Jersey and 

 Noi-ton Sound, Alaska. (Breeding south to Hudson's Bay and coast 



of Labrador.) 28. C. mandtii Light. Mandt's Guillemot. 



c^ Greater wing-coverts with at least their basal half black, this often 

 showing as a narrow bar beyond tips of middle coverts ; plumage 

 otherwise as in C. mandtii, and measurements nearly the same, but 

 bill larger and stouter; length 12.00-13.80, culmen 1.20-1.30, gonys 

 .55-.60i depth of bill at nostril .40-.45. Egg 2.25 X 1-55. Ilab. 

 Coasts of northern Europe; also from southern Greenland along 

 Labrador coast and south, in winter, to New Jerscj' ; breeding from 

 Newfoundland and southern Labrador to vicinitj' of Eastport, 



Maine(?) 27. C. grylle (Linn.). Black Guillemot. 



6'. Under wing-coverts smoky gray. 



Greater wing-coverts black basally, this increasing in extent toward 

 edge of the wing, where occu])ying almost the whole extent of the 

 outermost feather, thus producing a broad black " wedge" between the 

 two white areas; plumage otherwise as in C. grylle, with similar 

 seasonal changes, etc. ; length 13.00-14.00, wing C.90-7.30, culmeu 



