446 BULLETIN 50, UNITED STATES JSTATIONAL MUSEUM. 



As in many species of Arremon, all those of Arremonops have the 

 upper parts uniform olive or olive-green, the edge of the wing yellow, 

 and the under parts are likewise white medially and grayish or olive 

 laterallj'. 



The various species and subspecies belonging to this genus have 

 universally been referred to Erribernagra Lesson; but the type of the 

 latter {Emberiza platennh Gmelin) is exceedingly different in struc- 

 tural and other characters. In fact, it is difficult to understand whj' 

 these birds were ever associated with E. pJatensis and at the same time 

 so widely removed (placed in another " family "! ) from their very 

 close allies, the Arremones. 



The nearest ally of Emhernagra seems to be the South American 

 genus Emhe)'izoides Temminck (type Fringilla macroura Gmelin), the 

 type-species of the two genera differing from one another hardh' so 

 much as do certain species of Ammodramus. 



Compared with the so-called EmbernagrcB of Central America, the 

 genera Emhernagra (in its properly circumscribed sense) and Emheri- 

 zoidea differ as follows: 



a. Tail shorter than wing, with feathers not narrowed at tips; ninth primary shorter 

 than first (shorter than secondaries) ; exposed culmen much more than half 

 as long as tarsus; feathers of pileum normal; pileum with three broad stripes — 

 two black or brown lateral ones and a gray median one — or else wholly black 

 or chestnut; back not streaked. 

 6. Tail dusky, in contrast with color of back; chest with a pair of lateral black 

 patches or a complete black band; auricular and suborbital regions black. 



Arremon (p. 454) 

 hh. Tail olive or olive-green, concolor with the back; chest without black patches 



or band ; auricular and suborbital regions gray Arremonops (p: 445 ) 



aa. Tail longer than wing, with feathers narrowed at tips; ninth primary longerthan 

 third; exposed culmen not more than half as long as tarsus; feathers of pileum 

 with stiffened shafts; pileum narrowly streaked, without lateral or median 

 stripes; back conspicuously streaked (except in Emhernagra olivascens). 

 b. Tail exceeding wing by much less than length of tarsus, graduated for less than 

 length of the latter; gonys decidedly more than half the length of the man- 

 dible; culmen straighter Emhernagra (extralimital) 



66. Tail exceeding wing by much more than length of the tarsus, graduated for 

 nearly half its length; gonys not more than half the length of the mandible; 

 culmen more curved Emberizoides (extralimital) 



KEY TO THE SPECIES AND SUBSPECIES OF ARREMONOPS. 



a. Lateral crown-stripes chestnut or chestnut-brownish, sometimes streaked with 



black. 



6. Lateral crown-stripes lighter and duller brown, not sharply contrasted with the 



olivaceous median stripe. (Arremonops rufivirgatus. ) 



c. Paler and grayer, with more slender bill (depth at base not more than 7.62) ; 



flanks pale bufiy hair brown. (Northeastern Mexico and southern Texas. ) 



Arremonops rufivirgatus rufivirgatus (p. 447) 



cc. Darker and browner, with stouter bill (depth at base 8.13 or more); flanks 



deep buffy brown, approaching wood brown. (Southeastern Mexico.) 



Arremonops rufivirgatus orassirostris (p. 448) 



