NON-INDIGENOUS BRITISH BIRDS. 33 



Average measurement, '95 inch in length by 7 inch in 

 breadth. Incubation is performed by the female, but the 

 duration of the period is unknown. 



Diagnostic characters: It is impossible to give 

 any character by v/hich the eggs of the Calandra Lark 

 can be distinguished from those of the White-winged 

 Lark, but as a rule they are smaller. From those of the 

 Sky-Lark they may be separated by their more pyriform 

 shape and slightly larger size ; the markings are also 

 more scattered, and much more clearly defined. 



Family ALAUDID^. Genus Melanocorypha. 



WHITE- WINGED LARK. 



Melanocorypha sibirica {G?neHn). 



(British : Very rare abnormal autumn migrant.) 



Single Brooded. Laying season, late in April and in !NLay. 



Breeding area: South-central Palaearctic region. 

 The White-winged Lark has a somewhat restricted range, 

 and breeds in the extreme south-east of Russia from the 

 province of Stavrapol, north of the Caucasus, across the 

 steppes of Astrakhan and Saratov to Orenberg. East- 

 wards in Asia it breeds upon the Barabinska and 

 Kirghiz steppes to as far cast as the Great Altai. 



Breeding habits: The favourite- haunts of the 

 White-winged Lark are steppes bare of trees and open 

 grassy plains. In its habits, so far as they are known, it 

 very closely resembles the preceding species. In the 

 pairing season it may be seen constantly soaring in 

 short flights to sing. In the winter it is gregarious, but 



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