CLACK GUILLEMOT. 123 



nests, if the bare rock upon which the egg is placed can be 

 called a nest, and my Aleutian oarsmen were always in a roar 

 of laughter when one of these projectiles exploded on the head 

 of an unfortunate comrade." Mr. Trevor Battye informs me 

 that in Spitsbergen he saw this Guillemot swimming about 

 with the young one on its back. 



Nest. — None, the single egg being laid upon the bare rock. 



Eggs. — Similar to those of the Common Guillemot, and 

 subject to the same variation. Mr. H. J. Pearson visited a 

 colony on Novaya Zemlya, and obtained a series of eggs in 

 July, 1895. He says :—" The series shows great variety in 

 colour and size. In colour they closely resemble a selected 

 collection of the Common Guillemot's eggs, and pass from 

 pure white to the browns of the Razor-bill, with every variety 

 of yellows and blue-greens, some being very handsomely 

 blotched with black." 



THE BLACK GUILLEMOTS. GENUS CEPPIIUS. 



Cepphus^ Pallas, Spil. Zool. v. p. 2i7) (1769)- 



Type C. grylle (Linn.). 



The genus Cepphiis differs from the genus Uria in its 

 shorter bill, the culmen scarcely exceeding the length of the 

 inner toe and claw, in the differences of the summer and 

 winter plumages, and in the significant fact that it lays a 

 couple of eggs instead of one. 



L THE BLACK GUILLEMOT. CEPPHUS GRYLLE. 



Colynibiis gryile, Linn. Syst. Nat. i. p. 220 (1766). 



Uria grylle^ Macgill. Brit. B. p. 331 (1852) ; Dresser, B. Eur. 



viii. p. 581, pi. 623 (1877); B. O. U. List. Brit. B. p. 



207 (1883); Saunders, ed. Yarrell's Brit. B. iv. p. 81 



(1884); id. Man. Brit. B. p. 687 (1889); Lilford, Col. 



Fig. Brit. B. part xxiii. (1893). 

 Alca grylle, Seebohm, Hist. Brit. B. iii. p. 383 (1885). 

 {Plate CVIII.) 

 Adult Male in Summer Plumage. — Entirely black above and 

 below, including the quills and tail ; lesser wing-coverts black 



