264 NORTH AMERICAN BIRDS. 



A. Nostrils moderate, completely covered by incumbent feathers. 



a. Tail much longer than the wings; first primary attenuated, falcate. 



Pica. Head without crest. 



b. Tail about as long as the wings ; first primary not falcate. 



Cyanura. Head with lengthened narrow crest. Wing and tail 

 blue, banded with black. 



Cyanocitta. Head without crest. Above blue, with a gray patch 

 on the back. No bands on wing and tail. 



Xanthoura. Head without crest. Color above greenish ; the 

 head blue ; lateral tail-feathers yellow. 

 , Perisoreus. Head full and bushy. Bill scarcely half the head, 



with white feathers over the nostrils. Plumage dull. 

 B* Nostrils very large, naked, uncovered by feathers. 



Psilorhinus. Head not crested ; tail broad ; wings two thirds as 

 long as the tail. 



Calocitta. Head with a recurved crest ; wings less than half as 

 long as the tail. 



There is a very close relationship between the Jays and the Titmice, the 

 chief difference being in size rather than in any other distinguishing feature. 

 The feathers at the base of the bill, however, in the Jays, are bristly through- 

 out, with lateral branches reaching to the very tip. In Pariclce these feathers 

 are inclined to be broader, with the shaft projecting considerably beyond the 

 basal portion, or the lateral branches are confined to the basal portion, and 

 extended forwards. There is no naked line of separation between the 

 scutellse on the outer side of the tarsi. The basal joint of the middle toe 

 is united almost or quite to the end to the lateral, instead of half-way. 

 The first primary is usually less than half the second, instead of rather 

 more ; the fourth and fifth primaries nearly equal and longest, instead of the 

 fifth being longer than the fourth. 



Genus PICA, Cuvier. 



Coracias, Linn^tjs, Syst. Nat. 1735 (Gray). 



Pica, Bkisson, Ornithologia, 1760, and of Cuvier (Agassiz). (Tjrpe, Corviis pica, L.) 



Clei^es, Gambel, J. A. N. Sc. 2d Ser. I, 1847,47. 



Gen. Char. Tail very long, forming much more than half the total length ; the 

 feathers much graduated; the lateral scarcely more'than half the middle. First primary 

 falcate, curved, and attenuated. Bill about as high as broad at the base ; the culmen and 

 gonys much curved, and about equal; the bristly feathers reaching nearly to the middle 

 of the bill. Nostrils nearly circular. Tarsi very long ; middle toe scarcely more than 

 two thirds the length. A patch of naked skin beneath and behind the eye. 



The peculiar characteristic of this genus, in addition to the very long 

 graduated tail, lies in the attenuated, falcate first primary. Calocitta, which 

 has an equally long or longer tail, has the first primary as in the Jays 

 generally (besides having the nostrils exposed). 



