FALCONID.E — THE FALCONS. 



301 



head and neck, ed<;ed laterally with ligjht nilbiis; sccondai-ies passing: broadly into pale 

 ashy at ends; primaries slaty-brown, with obscure darker bands; no appearance of these, 

 however, on secondaries; rump entirely blackish-brown; upper tail-coverts wholly white. 

 Tail hoary slate, basal third (or more) white, the junction of the two colors irregular and 

 broken ; tip obscurely paler ; feathers obscurely blackish along edges, and with obsolete 

 transverse spots of the same; white prevailing on inner webs. Beneath entirely pure 

 white, scarcely variegated; tibia; and tarsi with a few scattered small transverse siiots of 

 blackish ; flanks with larger, more cordate spots of the same. (Breeds in this plumage.) 



Hab. Western North America from California to the Missouri, and from the Sas- 

 katchewan to Texas. 



Localities: Texas (Fort Stockton), (DRESSKn, Ibis, 1865, 325); Western Arizona (Corns. 

 Pr. A. N. S., 1866, 40). 



LIST OF SPECIMENS EXAMINED. 



Nat. Mus., 10; Philad. Acad., 2; Boston Soc, 2; Coll. R. Ridgway, 2. Total, IG. 



Measurements. 



wing. 



Sex.' 



$ 15.90-17.00 



Tail. 



9.50-10.50 



17.00-17.60 10.50-11.00 



1.00-1.18 



1.08-1.20 



Tarsus. 



3.10-3.45 



3.20 - 3.40 



1.40- 1.50 



1.60 - 1.65 



Specimens, 

 6 



The variations in tlii.s species are very slight, and never sufficient to mis- 

 lead the student. One specimen (26,590, <J ; Fort Tejon, Cal. ; J. Xantus) 

 differs from tlie adults described in liaving the abdomen quite closely barred, 

 the streaks on the breast distinct, the rufous above tinging tlie secondary 

 coverts, and spreading over the ujiper tail-coverts, wliile the tibise and tarsi 

 are of a very deep ferruginous, — the bars black. 



In a specimen from tlie Platte (5,577, i ; W. S. Wood) white prevails on 

 the tibiae, the bars being dark ferruginous upon a white ground ; the flanks 

 are similarly marked, the other lower parts, however, immaculate ; there is 

 much concealed white on the scapulars. The rufous tinge of the tail is very 

 deep, while there is a transverse series of black blotches, iudicatmg the 

 course of a transverse band near the end. 



Habits. The California Squirrel Hawk appears to be an e.xclusively 

 western species, occurring as far to the east as Nebraska and Kansas, and as 

 far to the nortli as the Plains of the Saskatchewan and Washington Terri- 

 tory. It occurs as far to the southeast as Texas, and has been found also 

 in New Mexico and in Arizona. 



This species was first noticed and described in a paper on the natural his- 

 torj'- of California published in the Transactions of the Pioyal Academy of Ber- 

 lin, in 1838, by Professor Liclitenstein, a Prussian naturalist. It was fir.st 

 brought to the notice of American naturalists by Mr. Edward M. Kern, of 

 Philadelphia, who accompanied Colonel Fremont in his expedition of 1846, 

 and who brought home specimens. 



Dr. Coues found it quite abundant about Fort Whipple, where it was 

 especially numerous in the winter, and where also he thinks it probable that 

 it is a permanent resident. He found it more generally frequenting mead- 



