OF THE HAMILTON ASSOCIATION 59 



J8. LARUS DELAWARENSIS Ord. 54. 



Ring-billed Gull . 



Adult plumage precisely like that of the Herring Gull, and its changes 

 substantially the same ; bill greenish-yellow, encircled with a black band near 

 the end, usually complete, sometimes defective, the tip and most of the cut- 

 ting edges of the bill yellow ; in high condition, the angle of the mouth and 

 ani a small spot bsside the black, red; feet olivaceous, obscured with dusky 

 or bluish, and partly yellow ; the webs bright chrome. Notably smaller than 

 argentatus ; length usually 18-20 inches ; extent, about 48 ; wing, about 15 ; 

 bill, tinder 2, and only about J deep at the protuberance; tarsus, about 2, 

 obviously longer than the middle toe. 



Hab. North America at large ; south in winter to Cuba and Mexico. 



Eggs 4 ; dark cream color, blotched with purple, umber, and black. 



This is one of the common Gulls which frequent Lake 

 Ontario during the winter, whose numbers helpto make up the 

 vast crowd which is frequently seen assembled on the edge of 

 the ice at the western extremit}' of the Lake, or in Hamilton 

 Ba}^, near the canal. 



In all stages of plumage it bears a strong resemblance to the 

 Herring Gull, but the ring round the bill and its smaller size 

 serve as distinguishing marks. 



19. LARUS PHILADELPHIA (Ord). 60. 

 Bonaparte's Gull. 



Tarsus about equal to middle toe and claw. Small ; 12-14 ; wing, 9J-18J; 

 tarsus, i^ ; bill, ij— ij, very slender, like a Tern's. Adult in summer : - Bill 

 black ; mantle pearly blue, much paler than matricilla ; hood slaty-plumbeous 

 with white touches on the eyelids ; many wing-coverts white ; feet chrome- 

 yellow, tinged with coral red ; webs vermilion. Primaries finally : — The first 

 5-6 with the shafts white except at tip ; first white, white outer web and ex- 

 treme tip black ; second white, more broadly crossed with black ; 3d to 6th- 

 8th with the black successively decreasing. In winter no hood, but a dark 

 auricular spot Young: — Mottled and patched abcve with brown or grey, 

 and usually a dusky bar on the wing ; the tail with a black bar, the primaries 

 with more black, the bill dusky, much of the lower mandible flesh colored or 

 yellowish, as are the feet. 



Hab. Whole of North America, breeding mostly north of the United 

 States ; south in winter to Mexico and Central America. 



Eggs scarcely known. 



