NON-INDIGENOUS BRITISH BIRDS, 157 



ment, 275 inches in length by 1-85 inch in breadth. 

 Incubation is performed by the female, but the duration 

 of the period is unknown. 



Diagnostic characters : The eggs of this Goose 

 cannot always be distinguished from those of the 

 Bernacle Goose, but from those of the White-fronted 

 Goose, which they also resemble in size and colour, they 

 may be separated by their lighter shell weight — eggs of 

 the same size beino; of course selected for the test. 



Family ANATID/E. Genus Bernicla. 



Sub-family ANSERINE. 



BERNACLE GOOSE. 



Bernicla leucopsis {Bechstein). 



(British : Common autumn and winter migrant.) 



Single Brooded probably. Laying season, probably June. 



Breeding area : North-western Palasarctic region. 

 The Bernacle Goose has been met with during summer 

 in Greenland, Iceland, Spitzbergen, and Nova Zembla, 

 and has been said to nest on the Loffoden Islands, but 

 its exact breeding grounds remain to be discovered. 



Breeding habits : Nothing is known of the breed- 

 ing habits and the nest of the Bernacle Goose. This 

 species has been said to breed on the Loffoden Islands, 

 and specimens of the eggs, together with a description of 

 the nest, were sent to Collett, but these eggs are certainly 

 too small. These islands are also far south of the usual 

 haunts of this Goose, which probably nests as far north 

 as land occurs. A description of the nest and the 



