224 
U. S P. R. R. EXP. AND SURVEYS—ZOOLOGY—GENERAL REPORT. 
List of specimens. 
Catal. 
No. 
Sex. 
Locality. 
When collected. 
Whence obtained. 
Orig’l 
No. 
Qdlleeted by— 
Length. 
Stretch 
of wings. 
Wing. 
Remarks. 
7618 
3 
Fort Steilacoom, W. T... 
April 17, 1858 
Dr. Suckley. 
13.0 
7621 
3 
114 
7.75 
12.50 
4.00 
7622 
3 
77 
4.00 
7625 
274 
12 00 
7636 
273 
7.50 
12. 
7634 
Dec., 1853. 
1930 
3 
2949 
o 
• 
5512 
V 
May 9, 1856 
772 
5513 
o 
170 
3907 
V 
s 
3908 
o 
5944 
6.75 
12.00 
4220 
Winterof’55 & ’6 
7632 
Q 
7631 
3 
4575 
24 
7633 
24 
5051 
Oct. 21, 1855 
151 
7.00 
12.50 
4.50 
black ; gums 
yellowish. 
7623 
5050 
Organ Mts., New Mexico. 
Mar. 9,1856 
178 
7.00 
13.00 
4.25 
eyes black; 
gums bluish. 
7624 
7637 
Jan. 31,1854 
Lieut. Whipple .... 
60 
4.00 
7638 
7635 
52 
75 
4020 
Q 
May, 1853. 
6.75 
11.50 
4.50 
SIALIA ARCTICA, Swain son. 
Rocky Mountain Blue Bird. 
Erythraca ( Sialia ) arctica, Swainson, F. Bor. Amer. II, 1831, 209 ; pi. xxxix. 
Erythraca arctica, Rich. List, 1837. 
Sialia arctica, Nuttall, Man. II, 1832, 573 ; I, 2d ed., 1840, 514.— Bonap. List, 1838 .—Aud. Synopsis, 1839, 84.— 
Ib. Birds Amer. II, 1841, 178 ; pi. 136.— McCall, Pr. A. N. Sc. V, June, 1851, 215. 
Sylvia arctica, Audubon, Orn. Biog. V, 1839, 38 ; pi. 373. 
Sialia macroptera, Baird, Stansbury Report Exp. Salt Lake, 1852, 314. 
Sp. Ch. —Azure blue above and below, brightest above ; the belly and under tail coverts white ; the latter tinged with blue 
at the ends. Female showing blue only on the rump, wings, and tail; a white ring round the eye ; the lores and sometimes a 
narrow front whitish ; elsewhere replaced by brown. Length, 6.25 ; wing, 4.36 ; tail, 3.00. (1875.) 
Hab. —High dry central plains ; Upper Missouri to Rock}'mountains range and south to Mexico. Rare on the coast of 
California. 
In this species there is none of the reddish brown of the two other American blue birds, the 
color throughout being blue, except as mentioned. The shade of blue is much lighter, with 
more green in it, or smalts-color, especially on the crown, instead of the purplish blue of the - 
others. The shade on the under parts is paler than above ; it extends entirely along the sides 
and to the abdomen. 
The female has the abdomen and under coverts like the male ; the remaining under parts, 
with the head, neck and hack, are light brown, although a bluish shade is appreciable on 
i 
