BIRDS — COEVIDAE — PICICOEVUS COLUMBIANUS. 



573 



Comparative measurements of species. 



PIOICORVUS COLUMBIANUS, Bon. 



Clarke's Crow. 



Corvus columbianus, Wilson, Am. Orn. Ill, 1811, 29 ; pi. xx.— Bon. Obs. Wilson, 1824, No. 38. — Ib. Syn. 1828, 



57.— NuTTALL, I, 1832, 218. 

 Xucifraga columbiana, Ann. Orn. Biog. IV, 1838, 459 ; pi. 362.— Ib. Syn. 1839, 156.— Ib. Birds Amer. IV, 1842, 



127 ; pi. 235.— Eon List, 1838.— Nuttall, Man. I, 2d ed 251. 

 Pieicorvus columbianus, Eonap. Consp. 1850,384. — Newberry, P. R. R. Rep. VI, iv, 1837, 83. 

 " Co: Hits megonyx, Wagler. " 



Sp. Ch. — Tail rounded or moderately graduated, the closed wings reaching nearly to its tip. Fourth quill longest ; secon 

 considerably shorter than the sixth. General color bluish ash, changing on the nasal feathers, the forehead, sides of head, 

 (especially around the eye,) and chin, to white. The wings, including their inner surface, greenish black, the secondaries and 

 tertials, except the innermost, broadly tipped with white ; tail white, the inner web of the fifth feather and the whole of the sixth, 

 with the upper tail coverts, greenish black. The axillars plumbeous black. Bill and feet black. 



1 ength of male, (fresh,) 12 inches ; wing, 7 ; tail, 4.30 ; tarsus, 1.20. 



Hab. — From Rocky mountains to Pacific. East to Fort Kearney. 



The tail of this species is nearly even, or but slightly rounded, the lateral feathers heing 

 ahout .20 of an inch shorter than the other white ones. Sometimes, however, the middle black 

 feathers project beyond the rest for nearly half an inch. 



There is considerable variation in the size of this species, as well as a striking difference in the 

 length of the bill. Thus, in 4460, from the Cascade mountains, the bill is nearly two inches long, 

 slender and attenuated, exceeding by half an inch that of 8239. The length is 12.50 inches ; 

 wing, 7.50 ; tail, 4.65. The general color is sometimes quite pale bluish ash, becoming appre- 

 ciably lighter on the head. The female is quite similar. 



List of specimens. 



