i38 COLYMBID^. 



THE BLACK-THROATED DIVER 



COLYMBUS ARCTICUS. 



Bill slightly curved upwards, with the middle of the lower mandible equal in 

 width to the base, exceeding three inches in length ; head ash-brown ; throat 

 and front of the neck black, lustrous with violet and green ; beneath the 

 throat a narrow band streaked with white and black ; sides and front of 

 the neck streaked with white and black ; back black, with a longitudinal 

 patch of white and black bars on the upper part ; scapulars with twelve or 

 thirteen transverse white bars ; bill dusky ; iris brown ; feet dusky, with 

 whitish membranes. Yoting birds have the head and back of the neck ash- 

 brown and the upper plumage dark brown, edged with bluish ash ; under 

 plumage white ; cheeks white, spotted with ash ; upper mandible ash-grey, 

 lower dull white. Length twenty-four to twenty-eight inches. Eggs dark 

 olive-brown, spotted with purplish brown. 



This Diver differs from the preceding species j)rincipally 

 in being of inferior size. The predominant tints of the 

 plumage are the same, and the habits of the two are so 

 similar that a separate description is unnecessary. The 

 present species is, however, far less common, though it has 

 been known to breed in the Outer Hebrides and in Scot- 

 land, where both eggs and young birds have been observed. 

 It lays two eggs, near the edge of a fresh-water loch ; and 

 Mr. Selby observed that a visible track from the water to 

 the eggs was made by the female, wdiose progress upon 

 land is effected by shuffling along upon her belly, propelled 

 by her legs behind. In the breeding season the old birds 

 are often seen on the wing, at which time also they have 

 a peculiar and loud cry, which has been compared to the 

 voice of a human beins in distress. 



