THALASSIORNIS LEUCONOTA. 



WHITE-BACKED DUCK. 



(Plate 63.) 



Clangula leuconotus, Smith, Cat. S. Afr. Mus., p. 37 (1837). 



Thalassiornis leuconota, Sharpe's ed. Layard Birds of S. Afr., p. 761 

 (1875-84) ; Nicolls & Eglington, Sportsman in S. Afr., p. 124 

 (1892) ; Salvadori, Cat. Birds Brit. Mus., xxvii, p. 436 (1895) ; 

 Woodward, Natal Birds, p. 212 (1899) ; Sclater, Ann. S. Afr. 

 Mus., ni, p. 352 (1905) ; Sclater & Stark, Birds of S. Afr., iv 

 p. 150 (1906). 



Thalassiornis leuconotus, Reichenow, Vogel Afrikas, i, p. 106 (1900-01). 



Description. The bird figured is a male. The sexes are alike. The 

 young birds are less oohraceous, and more brown on the abdomen. 

 Length about 17 in. 



Distribution. The White-backed Duck is confined to Africa and 

 Madagascar. It is found in Abyssinia, East Africa, Nyassaland, 

 to Cape Colony and as far west as Loango. 



Within South African hmits it is fairly widely distributed where 

 suitable conditions exist. Mr. Sclater states that it has not been 

 found in Rhodesia or on the Zambesi, but that it has probably 

 been overlooked. 



Sergt. Davies writes to me as follows : " These curious 

 little birds are not uncommon on some of the pans here in 

 Griqualand, and are usually to be found in small flocks of four 

 or five individuals. They are wonderful divers, going under 

 water without a ripple. They rise readily off tlie water, 

 although they paddle along with their feet for a httle way, 

 and when once fairly on the wing fly at a great pace, their 

 feet sticking out far beyond their tail, and all the time while 

 flying they utter their curious whistling note. 



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