FAMILY FORMICARIIDJE 



AA. Plumage plain, without streaks on upper parts, 

 a. Without spots on under parts, 

 b. Upper parts black. 



c. Under parts uniform black, a broad white 



band on greater wing coverts 



Microrhopias quixensis virgata, male 



cc. Under parts not uniform black but with 

 extensive patches of long white plume- like 



feathers on sides and flanks 



.... Myrmotherula axillaris albigula, male 

 bb. Upper parts blackist slate or olive. 



c. Upper parts blackish slate, a broad white 

 band on wing coverts, under parts rufous 



chestnut 



Microrhopias quixensis virgata, female 



cc. Upper parts olive brownish. 



d. Under parts buff 



Myrmotherula axillaris albigula, female 



dd. Under parts olive tawny 



Myrmotherula fulviventris, female 



aa. Conspicuously spotted on under parts. 



b. General coloring olive brownish, throat black 



with large white spots 



Myrmotherula fulviventris, male 



bb. Upper parts chestnut, under parts white with 



a band of spots on breast. 

 c. Throat black, the band on breast of heavy 



black spots 



Hylophylax n. ncevioides, male 



cc. Throat white tinged like chest with buff, 

 the band on breast of less heavy olive 



spots (4.95 in.) or more 



Hylophylax n. ncevioides, female 



II. Length 125 mm. (4.95 in.) or more. 



A. With bars, streaks or spots on upper or lower parts, 



or on both. 



a. Both upper and lower parts streaked, spotted or 

 barred; tail relatively longer; birds of thickets 

 and underbrush. 

 b. Both upper and lower parts barred. 



c. More coarsely barred on upper parts (sides 

 of head and neck, and throat streaked); 



plumage black barred with white 



Thamnophilus doliatus nigricristatus, male 



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