BIEDS OF KORTH AND MIDDLE AMBBIOA. 319 



KEY TO THE SPECIES AND SUBSPECIES OF CYANOLYCA. 



a. Throat bluish or silvery, abruptly contrasted both with black on sides (jf head 

 and color of chest, 

 h. Ohest bicolored (blue, crossed above by a band of black or white). (South 



American species, except C. pulchra.) 

 bb. Ohest unicolored (brown, black, or dull grayish blue), 

 c. Back and chest sooty brown; whole crown very pale blue or bluish white; 



throat purplish blue. (Cyanolyca pulchra. a ) 

 vc. Back and ohest black or blue; only part of the crown (if any) bluish; throat 

 silvery white or pale purplish blue. 

 d. Pileum and back black or dusky blue; chest black; depth of bill at nostrils 

 9 or more. (Highlands of Costa Rica, Chiriqui, and Veragua.) 



Cyanolyca argentignla (p. 319) 

 dd. Pileum, back, and chest blue; depth of bill at nostrils not more than 8. 



(Southeastern Mexico. ) Cyanolyca nana (p. 320) 



aa. Throat black or very dark blue, not abruptly contrasted (sometimes ooncolor) 

 with black of sides of head and color of chest. 

 b. Bill slender (depth at nostrils not more than 10); chest and hindueck blue; 

 crown and occiput purplish blue, like hindneck. (Guatemala; State of Chi- 

 apas, southern Mexico.) Cyanolyca pumilo (p. 321) 



bh. Bill stouter (depth at nostrils not less than 10.5) ; chest and hindneck black; 

 crown and occiput azure blue, abruptly defined, 

 c. Light blue occipital patch margined laterally with whitej neck brownish black 

 or blackish brown. (Southern Mexico; Guatemala.) 



Cyanolyca mitrata (p. 322) 



cc. Light blue occipital patch not margined laterally with white; neck black. 



(Highlands of Costa Rica and Chiriqui. ) Cyanolyca cucullata (p. 323) 



CYANOLYCA ARGENTIGULA (Lawrence). 

 SILVERY-THROATED JAY. 



Adults {sexes alike). — Head, neck, and chest black; anterior portion of 

 crown crossed by a band (about 6.3-7.6 wide) of pale grajdsh lavender 

 or silvery white, extending from each extremity backward in a nar- 

 row stripe, along each side of the crown and occiput to about the end 

 of the auricular region, the posterior portion of this streak of a 

 deeper lavender hue; entire throat (but not chin) pale lavender or 

 silvery white, forming a very conspicuous, sharply defined patch, 

 broader at its posterior extremity, where very sharply defined, with a 

 convex outline; lower back, scapulars, rump, upper tail-coverts, and 

 under parts posterior to chest dusky purplish blue, gradually shading 

 into the black anteriorly; wings and tail dull smalt or cyanine blue, 

 their under surface grayish black; bill, legs, and feet black. 



Young. — Similar to the adults, but the lavender marking on top of 

 head wanting or but slightly indicated, the whole crown and occiput 

 being dusky purplish blue. 



<^OyanociUa pulchra Lawrence, Ann. Lye. Nat. Hist. N". Y., xi, 1875 (pub. Feb., 

 1876), 163 (Quito, Ecuador; coll. G. N.Lawrence). — Sclater and Salvin, Proc. Zool. 

 Soc. Lond., 1876, 272 (crit.). — Taczanowski and Berlepsch, Proc. Zool. Soc. Lond., 

 1886, 116 (Quito). 



