THE GUILLEMOT. 567 



well as on the sides. In many instances, two birds are 

 found sitting each on its egg in the same hole. Both birds 

 work in digging the hole, using their bills and feet: they 

 also sit alternately on their egg, although the female engages 

 more industriously in this occupation, while the male labors 

 harder at the burrow. But one egg is laid : this is at first 

 pure-white ; but it soon becomes soiled and stained, and 

 appears to be a dirty yellowish-white. Its form is a pure 

 ovoidal. A number of specimens in my collection are from 

 2.48 to 2.30 inches in length, and from 1.70 to 1.65 inch in 

 their greatest breadth. Some specimens are marked with 

 spots and blotches of brownish-red, — the proportion of 

 marked ones being about two in five. 



Suh-Family Urin^. — The Guillemots. 



URIA, MOEHEING. 



Uria, MoERHiNG, Av. Gen. (1752). (Type Colymbus grylle, L.) 

 General form short and robust; head moderate; bill rather long, straight, some- 

 what compressed, pointed, angle of the under mandible distinct; nostrils in a groove 

 at base of upper mandible, the membrane of which is covered with short velvet-like 

 feathers; wings short, pointed ; tail short; legs short and robust; tarsus shorter than 

 the middle toe, compressed ; toes rather long, fully webbed; claws rather strong, 

 curved. 



UEIA GRYLLE. — ZaJ^am. 



The Guillemot. 



Alca grylle, Linnseus. Syst. Nat, I. (1758) 130. 



Uria grylle, Audubon. Orn. Biog., IIL (1835) 148; V. 627. 



Description. 



Bill straight, pointed; wing rather short, weak; first quill longest; tail short; 

 a large oval transverse space on the wing white, which is also the color of the under 

 wing coverts and axillary feathers, outer edge of the wing and shoulder brownish- 

 black ; all other parts of the plumage brownish-black, with a greenish tinge, and 

 darker on the back ; bill black ; feet red. 



Younger. — Under parts, neck, and rump, white ; head above and back dark- 

 brown; large space of white on the wing. 



Total length, about thirteen inches ; wing, six and half; tail, two inches. 



