162 WESTERN GULL. 



numerous small somewhat rectangular scales. Hind toe very small and 

 elevated; the fore toes rather long, the fourth little shorter than the third; all 

 scutellate above, and connected by reticulate webs; the lateral toes margined 

 externally with a thick membrane. Claws small, slightly arched, somewhat 

 compressed, blunt, that of the middle toe with the inner margin expanded. 



The plumage is full, close, elastic, very soft and blended, on the back and 

 wings rather compact. Wings very long, broad (four outer primaries only 

 partially developed); secondaries broad and narrowly rounded. Tail even 

 (not fully developed). 



Bill yellow, with an orange-red patch toward the end of the lower man- 

 dible. "Iris light hazel." Feet flesh-coloured, claws dusky. The head, 

 neck, lower parts, rump, and tail, are pure white; the back and wings light 

 greyish-blue, of a deeper tint than in L. argentatus; the edges of the wing 

 and the extremities of all the quills are white; the first seven quills are 

 greyish-black toward the end, that colour including the outer webs and the 

 greater part of the inner of the two first, and on the rest gradually diminish- 

 ing, so as on the seventh merely to form a subterminal bar; the first quill 

 with a patch of white on both webs near the end; the tips of all being white. 



Length to end of tail 25 inches (but the tail is not full grown); bill along 

 the ridge 2 T 7 2, along the edge of lower mandible 3^, its depth at the base \^ 

 at the angle j^; tarsus 2 {§; hind toe ff, its claw -ff ; second toe lyg-, its claw 

 T y, third toe 2^> its claw -ff; fourth toe 2y|, its claw -j 3 ? . 



Young Male. 



Bill flesh-coloured, beyond the nostrils and angle black, with the tips horn- 

 coloured. Feet flesh-coloured; claws brownish-black. The upper part and 

 sides of the head, the hind part and sides of the neck light brownish-grey, 

 mottled and streaked with white; on the back the colour is light greyish- 

 blue, some of the feathers mottled with brown, the adult plumage having 

 been partially assumed; the wing-coverts are chiefly of a greyish-brown 

 colour; the primary quills greyish-black, without white at the end; the 

 secondary blackish-grey, margined and tipped with white, finely undulated 

 with brown. The rump is white; the tail greyish-black, tipped with white; 

 the whole outer web of the outer, and the basal half of that of the next 

 feather white; the lower wing-coverts dusky-grey. All the lower parts are 

 greyish-white, obscurely mottled with pale brownish-grey. 



Length to end of tail 27 inches; bill along the ridge 2|-, along the edge of 

 lower mandible 3 T 2 2 -, its height at the base |§, at the angle ||; wing from 

 flexure 17i; tail Ik', tarsus 2j£; middle toe 2^, its claw -ff. 



From the above description, it will be seen that in proportions and colour- 

 ing this species does not difler much from L. argentatus. It is much 

 larger, however; its bill is deeper and stronger in a very conspicuous degree, 

 and its tarsi and toes are considerably longer. 



