10 



U. R P. R. E, 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. 



FALCO AURANTIUS, Gm. 



Fidco amrantiui, Gm., Syst. Nat. I, 283. (1788.) 

 F(dco Tujyularis, Datjdin, Trait d'Orn. II. 131. (1800.) 

 Falco thoracicm, Donovan, Naturalists' Kepository, II, (not paged, 1824.) 

 Falco aiadlalus, Swainson, Cab. Cy. p^ 340. (1838.) 

 Faho deiroleuem, Temmihok. 

 FiGBEBS.— Temm. PI. Col. 348 ; Donovan, Nat. Kep. II, pi. 45. 



About the size of, or rather smaller than F. eolumbarius. 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, tibias, 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 7J to 8, tail 4 to 4J inches. Female larger. 



Hab. Mexico, Texas, South America. Spec, in Nat. Mus. Washington, and Mus. Acad. Philadelphia. 



