FAMILY TILRAUPIDAE 



435 



of birds from this locality is uncertain. Another race is found on the 

 Caribbean slope of Costa Rica, where Slud (Bull. Amer. Mus. Nat. 

 Hist., vol. 128, 1964, p. 354) has observed it foraging for small fruits. 

 The only vocalization Slud ever heard was an occasional weak tsick. 



THRAUPIS EPISCOPUS (Linnaeus): Blue-gray Tanager, 

 Tangaro Azulejo 



Tanogra Episcopus Linnaeus, 1766, Syst. Nat., ed. 12, 1, p. 316. (Cayenne.) 



Medium size; body pale blue-gray, darker on back; lesser wing co- 

 verts bright royal blue; rest of wings and tail paler, near turquoise- 

 blue. 



Description. — Length 143-147 mm. Adult (sexes alike), head and 

 entire undersurface pale blue-gray; slightly darker on sides; back 

 darker blue-gray, sharply marked from nape, becoming bluer on rump 

 and upper tail coverts; lesser wing coverts shiny royal blue; middle and 

 greater coverts paler; primaries blackish, with outer web edged bright 

 blue, becoming increasingly dull, toward blue-gray, which is the color 

 of inner secondaries; tail feathers blue-gray, slightly brighter on edge 

 of outer webs; underwing coverts pale blue-gray. 



The Blue-gray Tanager is an abundant and widespread bird found 

 throughout Panama except in the higher mountains. It inhabits woods, 

 borders, shrubby clearings, and gardens; in towns it may become ex- 

 tremely tame. It is found on islands off both coasts, on two of which — 

 Coiba off the Pacific coast and Isla Escudo de Veraguas off the Carib- 

 bean — it has evolved distinct subspecies. 



The mainland race, cana, ranges north to southeastern Mexico and 

 south to northwestern South America. The populations of Mexico 

 through Panama have at times been separated under the name diaconus 

 Lesson 1842 (type locality, Realejo, Nicaragua). Hellmayr (Field 

 Mus. Nat. Hist. Zool. Ser., vol. 13, pt. 9, 1936, p. 244) expressed doubt 

 as to the validity of this form, and Blake ( Fieldiana: Zool., vol. 36, no. 

 5, 1958, p. 566) combined it with cana, in which he was followed by 

 Storer (in Peters, Check-list Birds of the World, vol. 13, 1970, p. 318). 

 The supposed differences in coloration of these taxa are not sufficient to 

 permit the consistent separation of individual specimens.* The race 



* Although Wetmore recognized the race diaconus, on the basis of darker dorsal 

 coloration, I believe that his decision resulted to a large extent from differences in 

 specimen preparation. Wetmore's skins from Panama are more compact, with the 



