NON-INDIGEAOUS BRITISH BIRDS. 89 



either under the shelter of a rock or an alpine bush. 

 It is cup-shaped, and made externally of grass stalks 

 and roots, and lined with moss, and exceptionally with 

 feathers, wool, or hair. Nothing appears to have been 

 recorded of the actions of this species at the nest. 



Range of egg colouration and measurement : 

 The eggs of the Alpine Accentor are from four to six 

 in number. They are of a pale turquoise blue without 

 markings of any kind. Average measurement, '95 inch 

 in length by -GS inch in breadth. Incubation is probably 

 performed by both sexes, but the duration of the period 

 is unknown. 



Diagnostic characters : The size and colour of 

 the eggs of the Alpine Accentor readily prevent them 

 from being confused with the other European species. 

 The locality is of some service too in their identification. 



Family CINCLID^. Genus Cinclus. 



B L A C K-B ELLIED DIPPER. 



Cinclus aquaticus melanogaster, Brehm. 



(British : Rare abnormal autumn migrant.) 



Single Brooded probably. Laying season. May and June. 



Breeding area : North-western PalcTearctic region. 

 The Black-bellied Dipper is not known to breed any- 

 where except in Scandinavia, Lapland, and Finland. 

 The Dippers breeding in the Baltic Provinces appear 

 to be undetermined. 



Breeding habits : It is not known that the habits 

 of the Black-bellied Dipper differ from those of the 



