NON-INDIGENOUS BRITISH BIRDS. i8i 



several observers. No nest beyond a thick warm bed of 

 down is provided. The bird is a close sitter, and when 

 flushed flies straight away at once. 



Range of egg colouration and measurement: 

 The eggs of the Golden-eye are usually from ten to 

 thirteen in number, but exceptionally as many as 

 nineteen have been found, probably the produce of two 

 females. They are smooth in texture, somewhat glossy, 

 and bright grayish-green in colour. Average measure- 

 ment, 2*3 inches in length, by I "6 inch in breadth. The 

 duration of the period of incubation is unknown. 

 Whether both sexes incubate is still undetermined. 



Diagnostic characters : The size, green colour of 

 the eggs, and situation of the nest combined with the 

 colour of the down are sufficient to identify the eggs of 

 the Golden-eye. The down is pale lavender-gray, with 

 obscure pale centres. The eggs of Barrow's Golden-Eye 

 are larger (average 2*4 by 172) and paler. 



Family ANATIDiE. Genus Somateria. 



Sub-family FULIGULIN^. 



STELLER'S EIDER. 



SOiMATERIA STELLERI [PaUas). 



(British : Very rare nomadic autumn and winter migrant.) 

 Single Brooded. Laying season, end of June and early July. 



Breeding area : North-eastern Paknearctic region, 

 and possibly the extreme North-western Palaearctic 

 region. Steller's Eider is only known to breed normally 

 and with certainty in Kamtschatka, on the islands in 

 Bering Strait, and the Aleutian Islands ; in the delta of 



