California Gull 17 



mounted male in the Colorado Mxiseum of Natural History at Denver, 

 taken at Valagoe Lake near Greeley, while Felger states that it is not 

 uncommon at Barr, where it is found associating with the Ringbills. 



California Gull. Larus calif ornicus. 



A.O.U. Checklist no 53 — Colorado Records — Morrison 89, p. 147 ; 

 Cooke 97, pp. 50, 192 ; Warren 09, p. 13. 



Description. — Adult — Mantle slaty -grey, rather pale and deHcate ; 

 rest of tho pliunage white ; primaries black, tipped with white, and 

 white and slaty -grey at tho bases ; the outer one with a large subapical 

 white spot across both webs and the shaft ; the second with a much 

 smaller subapical spot divided into two by the black shaft ; tips of 

 the secondaries white ; iris brown, eyelids yellow or red, bill chrome- 

 yellow with a bright vermilion patch at the angle of the lower man- 

 dible, followed by a transverse bar of black across both, feet bluish- 

 green, yellow on the webs. Length 20 ; wing 15*5 ; tail 5-75 ; culmen 

 1-80; tarsus 2-25. 



In winter the head and neck are streaked with dusky and the bill 

 is dull. Young birds are mottled with dusky, bufiy and grey ; the 

 wings and tail are blackish and the bill dusky with a black tip. 



Distribution. — Western North America from Alaska to Mexico, 

 breeding chiefly in the interior, especially on Great Salt Lake in Utah ; 

 wintering chiefly on the coast. 



The California Gull is an occasional or transient visitor to Colorado : 

 but has seldom been observed or obtained. 



Professor Wm. Osburn proctu-ed one specimen at Loveland, May 7th, 

 1890, and there are two examples in the Carter collection now in the 

 Denver Museiun of Natm-al History — one taken in Middle Park, April 

 28th, 1884, the other at Denver, October 26th, 1878. According to 

 Warren, C. H. Smith saw one at Coventry in 1905. This completes 

 the list of definite records. 



Ring-billed Gull. Larus delawarensis. 



A.O.U. Checklist no 54 — Colorado Records — Allen & Brewster 

 83, p. 198 ; Drew 85, p. 18 ; Woodbury 87, p. 116 ; Morrison 89, p. 147 ; 

 Cooke 97, pp. 18, 51, 192 ; Henderson 03, p. 234 ; 09, p. 225 ; Rockwell 

 08, p. 157 ; Warren 09, p. 13. 



Description. — Adult — Mantle pearly to pale slaty-grey, gradually 

 whitening on the secondaries ; head all round, under-parts and tail 

 white ; first primary black, with a white subapical spot divided by the 

 dark shaft, and with the basal haK of the inner web white ; second to 

 sixth primaries black with increasing pale basal portions and white 



