ALCIN^E. MERGULUS. ALCA. 215 



282. MERGULUS ALLE. LITTLE ROTCHE. 



In winter, the upper part of the head, a portion of the 

 cheeks, the hind part and sides of the neck, and all the upper 

 parts of the body, black ; the tips of the secondary quills, and 

 the margins of some of the scapulars, white, as are the 

 throat, fore-neck, breast, and abdomen ; the uppermost fea- 

 thers of the sides, with their inner webs, black, the lower 

 wing-coverts greyish-brown. In summer the colours similar, 

 but the throat and fore-neck brownish-black, like the head. 



Male, 9i, 14^, 4|, A, ,V, 1, A- 



This species occurs in summer in very high latitudes, and 

 in winter retires southwards, along the shores of both conti- 

 nents. Its food consists of small Crustacea and fishes, which 

 it procures by diving, its habits being similar to those of the 

 Guillemots and Auks. It is of rare occurrence in Britain. 

 I have seen two individuals on the Bass Rock, and have been 

 credibly informed that it breeds in considerable numbers at 

 St Abb's Head. In the winter season, it has several times 

 been obtained in England, 



Little Auk. Little Guillemot. Sea-Dove. 



Alca Alle, Linn. Sys. Nat. i. 211, Alca Alle, Lath. Ind. 

 Ornith. ii. 795, Uria Alle, Temnx. Man. d'Ornith. ii. 928. 

 Mergulus Alle, Little Rotche, MacGillivray, Brit. Birds, 

 ii. v, 



GENUS CXLIL ALCA. AUK. 



The Auks are very similar to the Guillemots, from which, 

 however, they are distinguished by the form of the bill, 

 which is as long as the head, stout, very hign, much com- 

 pressed, and obliquely furrowed on the sides ; the upper 

 mandible with the dorsal line decurved, the ridge extremely 

 narrow, the sides nearly flat, the nasal groove very large 

 and feathered, the edges sharp and inflected, the tip de- 

 curved, narrow, and obtuse ; the lower mandible with the 

 angle very narrow, and having a horny triangular appen- 

 dage, the sides toward the end erect and flat, the dorsal line 

 ascending and concave, the tip decurved ; mouth of mode- 

 rate width ; palate flattened with five prominent lines an- 

 teriorly ; tongue slender, trigonal, tapering, pointed ; oeso- 

 phagus wide, in its lower part, and the proventriculus enor- 

 mously dilated ; stomach small, elliptical, with the muscular 

 coat rather thin, the tendons round, the epithelium thin, 



