BRITISH BIRDS 



them has been pointed out by Howard Saunders [Manual of British Birds, 2nd ed. 

 p. 711), viz. that in the present species the upper part of the head and neck have a 

 greenish sheen, changing to purple below, whereas in the others these colours are 

 reversed. The streaks of white on the neck are also fewer in number and broader 

 in the white-billed species. 



Some five occurrences have been noted on the coast of England, and one in 

 Argyllshire, Scotland. It breeds in Novaya Zemlya and Northern Asia, and ranges 

 eastwards to the Arctic regions of the New World. 



In habits the two species appear to be alike, and in their winter plumage closely 

 resemble each other. 



THE BLACK-THROATED DIVER. 



Colymbus arcticus, Linnaeus. 

 Plate 77. 



Though breeding regularly in the more northern parts of Scotland, this beautiful 

 bird is not nearly so common off our shores in winter as the Great Northern Diver. 



It inhabits the northern parts of Europe, Asia, and America, and in winter 

 migrates to warmer waters, where in Europe it is found as far south as the Medi- 

 terranean and the seas of Southern Russia, in Asia ranging to Japan, and in 

 America to the Eastern United States. 



In Scotland it usually breeds on some island in a loch, sometimes a large sheet 

 of fresh water, such as Loch Maree, where I have seen the nest, at other times it 

 may be a comparatively small lake. 



The two eggs, greenish or reddish-brown in ground-colour, spotted with black 

 or brown, are laid in a slight hollow in a bed of herbage collected by the bird. 



Like the other members of this genus, the Black-throated Diver makes its nest 

 just at the water's edge, so that the bird when alarmed can quickly reach a place of 

 safety by sliding to the water. 



When watching the only nest of this species I have seen, which contained a 

 broken egg, apparently damaged by Gulls, one of the parent birds could be observed 

 quietly swimming around, and occasionally dipping its bill in the water. 



During the breeding season the cry is loud and harsh. 



The male and female are alike in colour, and in winter have the upper parts dark 

 greyish-brown, with the chin, throat, and under parts white. 



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