10 
U. 8. P. R. K. EXP. AND SURVEYS ZOOLOGY — GENERAL REPORT. 
feather edged with rufous. This stage is represented in Swainson's plate in Fauna Boreali — 
Americana. The adult has the upper parts entirely light bluish slate color ; nearly every feather 
with a black central line, and is even lighter colored and of more delicate and handsome shades 
than as given by Audubon. Between these well-defined and easily recognized stages there are 
other intermediate plumages impossible to describe, except in general terms. 
List of specimens. 
Locality. 
When collected. 
Whence and how 
obtained. 
Collected by — 
Measurements. 
I 1 
.2 -3 
6909 
5170 
5171 
4130 
5505 
4476 
4459 
4477 
5831 
5829 
5828 
5833 
5S32 
4588 
4500 
6875 
5483 
4475 
4615 
Nelson river, H. B 
Mouth Vermilion^on Mo. 
do do 
Oct, 25, 1856 
do 
Tamaulipas, Mexico 
El Paso, Texas 
Puget's Sound, W. T ... 
Cape Flattery, W. T 
Shoalwater Bay, W. T... 
Fort Steilacoom, W. T. 
do do 
Oct. 1, 1856 
Sept. 1, 1856 
do 
San Francisco, Cal 
California 
Petaluma, Cal 
Santa Clara, Cal .. 
Colorado river, Cal 
Mexico 
D. Gunn 
Lt. Warren 
do 
Lt. Couch 
Major Emory 
Dr. Cooper 
Lt. Trowbridge. 
Dr. Cooper 
Dr. Suckley 
do 
do 
do 
do 
Dr. Potts 
Lt. Williamson. 
do 
E. Samuels 
Dr. Cooper 
Major Emory 
J. Gould 
Dr. Hayden. 
do.--- 
12.75 
11.75 
12.00 
26. 7 
23. 75 
25. 00 
Dr. Newberry. 
Dr. Heerman . 
12.00 
13. 00 
13. 50 
25. 50 
26.13 
26. 25 
FALCO AURANTIUS, Gm. 
Fdco aurantius, Gm., Syst. Nat. I, 283. (1788.) 
Falco rufigularis, Dattdin, Trait d'Orn. II. 131. (1800.) 
■Falco thoracicvs, Donovan, Naturalists' Repository, II, (not paged, 1824.) 
Falco cucullatus, Swainson, Cab. Cy. p. 340. (1838.) 
Falco deiroleucus, Temminck. 
Figures. — Temm. PI. Col. 348 ; Donovan, Nat. Eep. II, pi. 45. 
About the size of, or rather smaller than F. columbarius. Entire upper parts bluish slate color, many feathers having darker 
centres, and concealed transverse bands of black. Throat, neck before, and breast yellowish white ; body beneath, black, with 
numerous transverse narrow bands of white ; abdomen, tibial, and under tail coverts dark rufous. Under wing coverts black, 
with numerous transverse bands and circular spots of white ; quills ashy black, with transverse bands of white on their inner 
webs ; tail black, the two middle feathers tinged with ashy, narrowly tipped with white, and with about seven irregular 
transverse bands of white ; bill horn color ; legs yellow. 
Total length — male — 9J to 10 inches, wing 7£ to 8, tail 4 to 4J inches. Female larger. 
Hab. Mexico, Texas, South America. Spec, in Nat. Mus. Washington, and Mus. Acad. Philadelphia. 
