Description oj a New Species of the Genus Larus. 79 



XV. — Description of a New Species of Bird of the Oenus LARUS 



Linn. 



By George N. Lawrence. Read March 7, 1854. 



Larus Californicus. 



The California^ Gull. 



Bill rather slender, and much curved; wings extending a 

 little beyond the end of the tail; legs and feet small; tail 

 even. 



Adult.— Bill yellow, upper mandible pale, except from the 

 base, as far as, and on a line with, the nostrils, where it is of a 

 dull green, just beyond the nostrils is a transverse blackish 

 mark, which reaches nearly to the ridge, under mandible bright 

 yellow, dusky on the sides, at the angle it is crossed by a black 

 spot or bar, bordered with reddish orange; the mark on the 

 upper mandible is opposite to this; head white, except the 

 crown and occiput, which are light ash, the feathers of the 

 hind part and sides of the neck have their centres blackish 

 ash ; neck, entire under plumage, rump and tail white ; mantle 

 and wings pearl-blue ; the six outer primaries are crossed by a 

 band of deep black, the first is almost entirely of this color, 

 but it gradually becomes less to the sixth, on which it is re- 

 duced to a narrow subterminal bar ; all the primaries are tipped 

 with white, on the exterior one the white is about two inches 

 in extent, and has a black bar dividing it near the tip, there is 

 a small white spot on the outer web of the second, next the 

 shaft, and about one inch and a half from the end ; the second- 

 aries terminate with white ; legs and feet (in the dried speci- 

 men) dull greenish yellow; claws black. 



Total length of skin, 23 inches; wing, from flexure, 15* ; 

 tail, 65 ; bill, along ridge from front base to point, 2, from 



