404 NATATORES. COLYMBUS. 



greenish-black, inside livid, and tinged with flesh-red. 

 Asperities on the hinder edge of the tarsus prominent, 

 and sharp-pointed. Head, chin and throat, nape and 

 back part of the neck, glossy black, with a slight tinge 

 of green. Auriculars, sides of the neck, and middle of 

 the fore part of the neck, rich orange-brown. Breast, 

 sides and flanks, glossy blackish-grey, the latter having 

 the lower parts of the feathers and the down pale red- 

 dish-brown. The rest of the under plumage silky 

 white, intermixed with blackish-grey. Upper plumage 

 glossy black, tinged with oil-green. Secondary quills 

 having their bases, and the greater part of the webs, 

 white. 



Fig. 2. Represents the immature bird, destitute of the 

 orange-brown upon the neck, and having the chin white. 

 The upper plumage is also lighter in colour, and the 

 belly and abdomen are pure white. 



GENUS COLYMBUS, LATH. DIVER. 



GENERIC CHARACTERS. 



BILL rather longer than the head, strong, strait, com- 

 pressed, and sharp pointed ; the upper mandible slightly ex- 

 ceeding the lower one in length. Tomia of both mandibles 

 bent inwards and sharp. Nostrils basal, lateral, linear, ob- 

 long, pervious, half closed by a membrane. 



Wings short, acuminate, having the first quill-feather the 

 longest. Tail short and rounded. 



Legs abdominal, or placed at the further extremity of the 

 body, with the tibiae concealed within the integument. Tarsi 

 thin, very much compressed. Feet large, of four toes, three 

 before and one behind ; outer toe exceeding the middle one 



