BIRDS FALCONINAE — KALCO COLUMBARIUS. 9 



Sub-Genus Hypotiiorcliis. 

 FALCO COLUMBARIUS, Linnaeus. 



Pigeon Hawk. 



FakocolunAariiis, LiXN. Syst. Nat 1,128, (176G.) 

 FaUo inUrmiitua, DAirmN.Tmito d'Orn. II, Ul, (1800.) 

 Faleo temrrarius, Ali)iBON,Orn. Biog. I, 381, (1831.) 

 FaUo Auduboni, Rlacewaix, Researches, Zool. 1834. 



Fiomra — Catesby's Carolina, pi. 3 ; Vieill. Oia. d'Am., Sept. pi. 11 ; AVilson Am. Orn. II, pi. 15, fig. 3 ; Swains. Fuiin. 

 Bor. Am. Birds, pi 25 ; Aud. B. of Am., pi. 75, 92, oct. ed. I, pi. 21 ; De Kay Nat. Hist., N.Y., Birds, pi. 4, fig. 9. 



Adult Male. Entire upper parts bluish slate color, every fciither with a, black Iongitu<linal line ; forehead and throat 

 white, other under part.-; pale yellowish or reildish wliite ; every feather with a longitudinal line of brownish black ; tibiiB 

 light ferruginous, with lines of black. (Juills black, tipped with ashy white ; tail light bluish ashy, tipped with white and 

 with a wide subterminal band of black, and with several other transverse narrower bands of black ; inner webs nearly white ; 

 cere and legs yellow ; bill blue. 



Youngfr. Entire upper plumage dusky brown, quite light in some specimens, and with a tinge of ashy ; head above, with 

 narrow stripes of dark brown and ferruginous, and in some specimens many irrugular spots and edgings of the latter color 

 on the other upper part*. Forehead and entire under parts dull white, the latter with longitudinal stripes of light brown ; 

 sides and flanks light brown, with pairs of circular spots of white ; tibi« dull wliite, with dashes of brown ; tail pale brown, 

 with about six transverse bands of white. Cere and legs greenish yellow. 



Yuung. Upper plumage brownish black, white of the forehead and under parts more deeply tinged with reddish yellow ; 

 dark stripes wider than in preceding ; sides and flanks with wide transverse bands of brownish black, and with circular 

 spots of yellowish white. Qui31s black; tail brownish black, tipped with wliite, and with about four bands of white ; cero 

 and feet greenish yellow. 



Total length. Female, 12 to 14 inches; wing, 8 to 9 inches ; tail, 5 to 5J inches. Male, total length, 10 to 11 inches; 

 wing, 74 to 8 inches ; tail, 5 inches. • 



IIiJi Temperate North America, Mexico, Central America, Northern South America. Spec, in Nat. Mus. , Washington, 

 and Mus. Acad. , Philadalphia. 



Specimens in the present collection show that this little hawk inhabits the entire coast of the 

 possessions of the United States on the Pacific ocean. Being, also, one of the most abundant 

 species of its family in the States on the Atlantic, its locality may he stated as the whole of 

 temperate North America. 



This bird presents the usual variations in plumage which prevail in nearly all tlie birds of 

 the family Falconidfe, and render the determining of species frequently perplexing and difficult. 

 There are, however, three well-defined stages exhibited in a large number of specimens now 

 before me, including the specimens in the present collection, as given above, and others from 

 various parts of the United States. Of these the adult is easily distinguished, and is very 

 nearly as figured by Audubon, under the name Falco temerarius, but of the other two pluma"-es 

 we cannot at present determine which is the more mature. One of the latter is dull brown, as 

 figured in Fauna Boreali Americana, as above, and the other much darker and nearly black, as 

 in the plates of Wilson Am. Orn., and Aud. B. of Am., as above cited. 



The darkest colored specimens that we have ever seen are in this collection, and so difierent 

 from the adult as to readily suggest doubts of their specific identity. Both males and females 

 are clear brownish black, and in one specimen, a male obtained by Dr. Cooper, at Shoal water 

 bay, "Washington Territory, the tail is without a vestige of the spots u.sually to be noticed, and 

 there are very few on the primaries. This is probably the youngest plumage. 



Another plumage is uniformly dull and frequently pale brown above, with nearly every 

 2b 



