826 LAKUS 



ad. (Bosphorus). Differs from L. ridibundus in having the hood jet 

 black ; a small crescentic white patch above and one below the eye ; the 

 bill rather stouter and larger ; quills white, the first only externally mar- 

 gined with black ; bill and legs red ; iris brown. Culmen T6, wing 12'0, 

 tail 5'0, tarsus 1*9 inch. In winter it differs from L. ridibundus in the 

 coloration of the primaries, and the nape and hind neck are much more 

 striated, not clouded, with grey. 



Hob. The coasts of the Black Sea and Mediterranean, Spain, 

 Portugal, and South France, straying north as far as England, 

 where it has been obtained once or twice, and the mouth of the 

 Somme, in Northern France. Winters as far south as Nubia. 



In habits it resembles L. ridibundus, but its cry, though very 

 similar, may be distinguished by a practised ear. It breeds 

 in the eastern portion of its range, on sand-banks and in 

 lagoons, its nest being constructed of seaweed and grass, and in 

 May, or early in June, 2 to 3 eggs are laid, which vary in 

 ground-colour from white to pale stone-ochreous, with pale 

 inky shell-markings and blackish brown surface spots, blotches, 

 and scratches. In size they measure about 2 '28 by 1'55. 



1136. BONAPARTE'S GULL. 

 LARUS PHILADELPHIA. 



Larus philadelpJiia (Ord), in Guthrie's Geogr. 2nd Amer. ed. ii. p. 319 

 (1815) ; (Gould), B. of Gt. Brit. v. pi. 65 ; (Newton), P.Z.S. 1871, 

 p. 57, pi. iv. fig. 6 (egg) ; Dresser, ix. p. 387, pi. 717 ; Saimders, 

 Cat. B. Br. Mus. xxv. p. 185 ; id. Manual, p. 661 ; Ridgway, p. 36 ; 

 Lilford, vi. p. 35, pi. 17 ; L. bonapartii, Swains, and Richards. Faun. 

 Bor. Am. Birds, p. 425, pi. 72 (1831). 



ad. (Canada). Head and neck dark plumbeous black ; a narrow, 

 interrupted white line round the eye ; mantle dark French-grey ; lower 

 neck, upper tail-coverts, tail, and entire under parts white ; 1st primary 

 white, but black on the outer web and across the tip, 2nd black across the 

 tip and a little way np the edge of the inner web, the 3rd and 4th with 

 broad subterminal black bands and white tips, pearl-grey on the inner 

 webs, the rest up to the 7th grey with black subterminal bars, the 7th and 

 8th grey with a small dark margin at the end of the inner web ; bill deep 

 black ; legs and feet orange-red ; iris dark brown. Culmen T6, wing 10'3, 

 tail 4'0, tarsus 1*38 inch. In winter the head and neck are white, slightly 

 marked with grey, a grey spot on the ear-coverts, the legs flesh-coloured. 



Hcib. North America, breeding in the Fur countries and 

 found in winter as far south as Bermuda ; a rare straggler to 

 Europe, having been obtained about six times in Britain, and 

 once in Heligoland. 



