426 



BRITISH BIRDS. 



been obtained on the Galapagos Islands, some of the Pacific islands, and 

 on the coasts of New Zealand and Australia. When the breeding-season 

 is over, these birds wander far and wide over the surface of the oceau, and 

 it is quite probable that they may occasionally round the Cape of Good 

 Hope or Cape Horn, so that their winter area of distribution may be 

 regarded as continuous. With the exception of the examples obtained off 

 the British coast, the Dusky Shearwater is not known to have occurred in 

 Europe; but on the American coast it has been obtained as far north 

 as New York. 



The Dusky Shearwater is said to breed, in company with its near ally 

 the Manx Shearwater, on the Azores and the Canaries, and its eggs have 

 been obtained on the Desertas, a group of islands near Madeira. It 

 resembles the latter bird in all its habits. Its note resembles that of its 

 ally, and has been expressed as pemlyco. It breeds in the same way, and 

 lays a single pure white egg, Avhich varies iu length from 2'3 to 2*0 inch 

 and in breadth from 1'45 to 13 inch. 



The Dusky Shearwater only differs from the Manx Shearwater in being 

 slightly smaller in size (wing 8 inches or under) and in having the white 

 of the uuderparts extending on the lores and over the entire ear-coverts 

 up to and behind the eyes. It is not known that there is any difference iu 

 the changes of plumage which the two species undergo. 



The Dusky Shearwater, like some of its congeners, appears to vary in 

 the colour of its under tail-coverts from white to brown ; and Baird, Brewer, 

 and Ridgway have separated the two forms uuder the impression that the 

 whiter examples were confined to the Pacific ; but as the collection of 

 Salvin and Godman contains examples of both forms from the Pacific, it 

 seems probable that there is no geographical distinction between them. 





