California Gull 17 
mounted male in the Colorado Museum 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 californicus. 
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 delicate ; 
rest of the plumage white; primaries black, tipped with white, and 
white and slaty-grey at the 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 ; culmeni 
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, buffy 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 procured one specimen at Loveland, May 7th, 
1890, and there are two examples in the Carter collection now in the 
Denver Museum of Natural 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. Zarus 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 half of the inner web white; second to 
sixth primaries black with increasing pale basal portions and white 
Cc 
