116 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 



gg. Tail less than half as long as wing, slightly rounded, the rectrices 



not narrowed terminally (though subacuminate at tip); inner 



webs of rectrices yellow or red, the outer webs green (both webe 



blue terminally). 



h. Head normally flattened (only the orbital region naked and lores 



scantily feathered) Pyrilia (p. 201). 



Kh. Head (all round) naked as far back as ears, scant short bristles re- 

 placing feathers Gypopsitta (extralimital).a 



ee. Larger (wing more than 150 and if less than 170 mm. the under wing- 

 coverts not red but under tail-coverts with red. 

 /.Tail less than half as long as wing, slightly double-rounded or faintly 

 emarginate, the rectrices narrowly rounded or subacuminate at tip; 

 under tail-coverts red; feathers of lower neck smaller (normal). 



Pionus (p. 206). 



ff. Tail not less than half as. long as wing, more or less (usually slightly) 



rounded, the rectrices broadly rounded at tip; under tail-coverts 



without any red; feathers of lower neck (especially hindneck) larger 



and broader, sometimes developed into a distinct erectile ruff. 



Amazona (p. 217). 

 dd. Tail at least two-thirds as long as wing. 

 e. Mandible as in Amazona but relatively deeper and with tip emarginate 

 instead of rounded; orbital region extensively naked; feathers of sides 

 of head acicular, those on nape very long and broad, forming a very con- 

 spicuous erectile ruff; tenth (outermost) primary equal to fourth; tail 

 more strongly rounded, the rectrices very broad; coloration varied (under 

 parts and nuchal crest purplish red, the feathers tipped with blue, head 

 brown streaked with whitish, the forehead dull 'whitish). 



Deroptyus (extralimital).* 

 ee. Mandible unique in its flattened sides margined beneath by a distinct 

 curved ridge, the under side with a distinct median ridge, the tip 

 recurved almost at a right-angle with the axis; orbital region mostly 

 feathered; feathers of head and neck normal, those of nape rather 

 short; tenth (outermost) primary longer than sixth; tail less strongly 

 rounded, the rectrices rather narrow; coloration simple (plain green 

 with violet on abdomen : Triclaria (extralimital). 



o Gypopsitta Bonaparte, Naumannia, 1856, Consp. Psittacorum, genus 25. (Type, 

 Psittacus vulturinus Kuhl.) — Cfypopsittacus (emendation) Salvadori, Cat. Birds Brit. 

 Mus., xx, 1891, 349. 



Lower Amazon Valley. (Monotypic.) 



Except in its naked head this genus agrees perfectly in details of structure as well 

 as in style of coloration with Pyrilia. 



& Deroptyus Wagler, Mon. Psitt., 1832, 492. (Type, Psittacus accipitrinus Linnseus.) 

 Derotypus (emendation) Bonaparte, Consp. Gen. Av., i, 1850, 5. 



Amazon Valley and Guiana. (Monotypic.) 



* Triclaria Wagler, Mon. Psitt., 1832, 499. (Type, Psittacus cyanogaster Vieillot.)— 

 Maximilicus "Lessfon]" Gray, List Gen. Birds, 1840, 51. 



Southeastern Brazil. (Monotypic.) 



