CHERRIE ; ORNITHOLOGY OF THE ORINOCO REGION. 257 



I believe all the species found in our region are permanent residents 

 there. Several of the forest frequenting species such as those that 

 pertain to the genera Philydor, Xenops, and Automolus are commonly 

 found in the small flocks of birds (made up of many unrelated forms) 

 that wander aimlessly about the forests and that are so characteristic 

 of bird life in the tropics. 



KEY TO THE GENERA, SPECIES AND SUBSPECIES OF FURNARIIDAE. 



a. Maxilla with tip not at all decurved; mandible strongly recurved ter- 



minally.. . Xenops genibarbis. 



a . Maxilla with tip more or less decurved and mandible not recurved ter- 

 minally. 



b. Nostrils decidedly operculate, opening a narrow longitudinal slit. 

 c. Breast streaked, the feathers with buffy shaft streaks. 



d. Tail short, slightly rounded; outstretched feet reaching to end of 



tail Microxenops milleri. 



d'. Tail long, graduated ; outstretched feet falling far short of end of 



tail Thripophaga cherriei. 



c . Breast feathers without buffy shaft streaks. 

 d. A distinct, yellow, yellowish, black or blackish chin spot. 



e. Breast hazel brown chin and upper throat blackish Synallaxis rutilans. 



e'. Breast not hazel. 

 /. Crown chestnut brown, in sharp contrast with remaining 



upper parts Siptornis hyposticta. 



f . Crown practically uniform in color with back. 



g. PrimanMiiillswith distal half (more or less) of inner webs 

 blackish, the line between that and the rufous basal por- 

 tion being abruptly transverse Synallaxis cinnamomea. 



g'. The blackish color of the distal part of the inner webs of 

 theprimariesextends well toward the base of the Quills along 

 the shaft, the line between the blackish tips and rufous 



base extending diagonally across the web of the feathers . . Synallaxis gujanensis. 

 d'. Chin spot (if present) neither yellowish nor blackish. 



e. General color of upper parts bright hazel brown (pileum 



darker) Synallaxis vulpina alopecias. 



e'. General color of upper parts buffy-brown, or olive-brown with 

 rufous wash. 



/. Tail brown, nearly uniform with back Synallaxis albescens albigul- 



aris. 



/'. Tail nearly walnut brown, not uniform with back Synallaxis gujanensis gujan- 

 ensis. 



b'. Nostrils not operculate (opening not slitlike), rounded, opening 

 upward. 



c. General color of under parts bright raw sienna Philydor pyrrhodes. 



c'. General color of under parts buffy-brown, olive buff, or dusky 



tawny olive. 

 d. Feathers of crown (slightly elongated) and occiput chestnut, 



very distinct from the rusty raw-umber of the back Philydor rufipilea.us como' 



brinus. 

 d'. Feathers of crown and occiput nearly concolor with back, not 



chestnut. 

 . A well denned buffy-yellow superciliary'stripe extending from 



the bill to the occiput; throat reed yellow Philydor ruficaudalus. 



e'. No superciliary stripe, or, if present, not well developed, and 



throat not reed yellow. 

 /. General color of under-parts tawny olive brown, paler in the 



centre; chin and upper throat pinkish buff Aulomolus turdinus. 



/'. General color of under-parts without tawny shade; chin, 

 throat and middle of breast cartridge buff (Ridgway's); 



sides dusky olive-brown A utomolus infuscatus cervical- 



J, 



SYNALLAXIS ALBESCENS ALBIGULARIS Sclater. . 

 Synallaxis albicjulans Scl.. P. Z. S. 1858. p. 63. 

 Synallaxis albescens albigularis Berlepsch & Hartert, p. 59. 



Noted from the delta region at Las Barrancas up as far as the 

 mouth of the Apure River. 



