376 BIRDS OF TUNISIA 



been met with on the coasts of the Kegency in winter. It is, 

 however, probably very rare and merely an accidental strac;gler to 

 Tunisia, and in most parts of the Mediterranean. 



Loche includes the species among the birds of Algeria, and a 

 specimen from that country is preserved in the Milan Museum under 

 th3 Eegister No. 17796. 



According to Favier this Gull is found about the Straits of 

 Gibraltar in small numbers from January to March, immature birds 

 only having been seen by him, and Colonel Irby states that Favier's 

 observations agree with his own. 



The Great Black-backed Gull inhabits Iceland and the Faroes, 

 ranging across Northern Europe eastward to the Petchora Eiver, and 

 southward along the west coast of France, where it breeds, as far as 

 the Mediterranean, where it is more or less rare, and to the Canaries, 

 on some of which islands it is said to be connuon. Across the 

 Atlantic it is found in Danish Greenland, and along the east coast of 

 North America, ranging southwards to Florida in winter. 



In its habits this species appears to be more unsociable than most 

 other Gulls, and extremely wary and suspicious. All authors agree 

 in calling it very predatory and a great robber of other birds' eggs and 

 young, so much so that it is looked upon as a great pest, and in some 

 countries is taxed as a bird of prey. 



RISSA TRIDACTYLA (Linna;us). 

 KITTIWAKE. 



Larus rissa, Linn. Stjst. Nat. i, p. 224 (1766). 



Larus tridactylus, £;'««. Syst. Nat. i, p. 221(1766); Malhcrhc, Fauna 



Orn. dc VAhj. p. 35 (1855). 

 Rissa tridactyla, BonajJ. Comp. List Birds Eur. and N. Amcr. p. 02 



(183«); Lochc, Expl. Sci Alij. Ois. ii, p 185 (1867); Kocnig, J. f. O. 



1888, p. 284 ; id. J. f. 0. 1893, p. 95 ; Saunders, Cat. Birds Brit. Mus. 



XXV, p. 305. 



Description. — Adult male, winter, from Tunis, North Tunisia. 



Head, nape, rump, tail and under parts white ; a grey patch on each 

 side of the head behind the eye ; rest of the upper parts French-grey, rather 

 whiter across the mantle; primaries pearl-grey, becoming black at the tips, 

 and some of them with small white spots at the tips. 



