Western Grebe 5 
sometimes floating, sometimes built up from the shallow 
bottom ; the eggs, four to five, are dull bluish-white 
and measure 2°31 x 1°52. 
Genus COLYMBUS. 
Bill moderate, rather stout, hardly compressed, about equal to or 
less than the head, culmen usually slightly decurved at tip; middle 
toe and claw exceeding the culmen and the tarsus ; neck moderately 
long ; head with a crest, or ruff or both. 
A large cosmopolitan genus with four species in the United States. 
Key or THE SpEcizs. 
a. Larger, with a longer bill, culmen over 2:0; throat white, part 
of neck rufous. C. holbeelli, p. 5. 
b. Smaller with shorter bill, culmen under 1:5. 
a’ Throat and neck black or dusky. C. n. californicus, p. 6. 
bt Throat dusky ; neck rufous. C. auritus, p. 6. 
ct Throat and neck dirty white. C. auritus, heims et juv, p. 6. 
Holboell’s Grebe. Colymbus holbelli. 
A.O.U. Checklist no 2—Colorado Records—Drew 85, p. 18 ; Morrison 
88, p. 140; 89, p. 146; Cooke 97, pp. 49, 155. 
Description.—Adult—Crown (which bears a very short crest and 
inconspicuous ruffs) and nape greenish-black, a line down the neck 
and upper-parts black, with brown on the wings; sides of the head 
and throat silvery ash; neck, except along the dorsal line, rufous ; 
lower-parts silvery white, somewhat dappled; iris carmine, bill black, 
yellowish on the lower mandible. Length 19:0; wing 7°60; culmen 
2:10; tarsus 2°50. . 
Young birds, and adults in winter, have the rufous of the neck 
replaced by ashy-brown or grey, the sides of the head and throat pure 
white, and the bill chiefly yellow. 
Distribution—Breeding from eastern Asia and Greenland, south to 
the northern row of states from, Washington to Minnesota ; in winter 
south to South Carolina and Monterey Bay in California. 
The status of this bird in Colorado is rathdr indefinite. It is noted 
by Drew and Morrison as occurring in the south-western part of the 
State, but without any definite statement. On the other hand it 
has been obtained by Bond on lakes near Cheyenne in autumn. This 
is actually in Wyoming but only a few miles from the State border. 
It will probably be found to be a rare fall-migrant in the north-eastern 
part of the State. 
