210 Birds of Colorado 
The Horned Owl in Colorado makes use, as a rule, of 
an old Magpie’s or Red-tailed Hawk’s nest, in which to 
lay its eggs. Warren noticed it however nesting in a 
hole in a sandstone bluff at Gaume’s ranche in Baca co. 
Gale found it a most persistent layer ; he took three sets 
of eggs from the same pair of birds ; the sets numbered 
four, three and two respectively, and the nest-site was 
changed each time. Incubation, which is undertaken 
entirely by the female, lasts about four weeks. The 
eggs, usually four in number, are rounded ovals, white 
in colour and not very glossy ; they measure 2°2 x 1°90. 
This Owl is one of our earliest breeders ; Gale found 
fresh eggs between March 10th and 25th; any found 
later, he believed to be second or third layings, due to 
failure or robbery of the first set. 
Genus NYCTEA. 
Owls of large size—wing 15 to 18—with plumage mostly white ; re- 
sembling Bubo in, other respects, but with the ear-tufts rudimentary 
or wanting, and the bill and claws almost entirely concealed by the 
dense growth of the frontal and toe feathers. 
Only one circumpolar species is comprised in this genus. 
Snowy Owl. Nyctea nyctea. 
A.O.U. Checklist no 376—Colorado Records—Morrison 89, p. 67; 
Cooke 94, p. 183 ; 97, pp. 80, 161, 206; H. G. Smith 96, p.76; Hender- 
son 03, p. 235; 09, p. 230. 
Description.—Male—Pure white above and below, sometimes immacu- 
late, more generally marked with transverse spots or bars above and 
below ; the face, throat and feet usually the least marked. Iris yellow ; 
bill and claws black. Length 22-0; wing 15-5; tail 9-25; culmen 
1-50; tarsus 1-8. 
The female is larger—wing 17-3, tail 10-0—and much darker, only the 
face, throat and middle of the breast and feet immaculate; top of the 
head and hind-neck spotted, rest of the body barred with dark brown. 
Distribution.—Breeding in the Arctic regions of both hemispheres, 
in America north of 53°, from Alaska to Labrador; south in winter, 
more or less regularly, to the northern and middle states; more 
common in the east. 
