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 recur\'ed ter- 
minally Xenops genibarbis. 
a'. Maxilla with tip more or less decurved and mandible not recurved ter- 
minally. 
6. 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 wiihoui 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 Siplorriis hyposticta. 
/'. Crown practically uniform in color with back. 
g. Primary quills with distal half (more or less) of inner webs 
blackish, theline 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 
theprimariesextendswelltoward the baseofthequills along 
the shaft, the line between the blackish tips and rufous 
base extending diagonally across the w^eb of the feathers . . Synallaxis gujanens's. 
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- 
/'. Tail nearly walnut brown, not uniform with back. . Synallaxis gujanensts gujan- 
b'. Nostrils not operculate (opening not slitlike), rounded, opening 
c. General color of under parts bright raw sienna Philydor Pyrrkodes, 
c'. General color of under parts buflty-brown. olive buff, or dusky 
d. Feathers of crown (slightly eloneated) and occiput chestnut, 
ver\' distinct from the rusty raw-umber of the back Philydor rufipHea.us conso- 
brinus. 
d'. Feathers of crown and occiput nearly concolor with back, not 
chestnut. 
e. A well defined buffy-yellow superdliar>-rstripe extending from 
the bill to the occiput; throat reed yellow Philydor rnficaudatus. 
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 Automolus lurdi mis. 
f. General color of under-parts without tawny shade; chin, 
throat and middle of breast cartridge buff (Ridgway's); 
sides dusky olive-brown A utomolus infuscalus cervical- 
Synallaxis albescens albigularis Sclater. 
Synallaxis albigularis Scl., P. Z. S. 1858. p. 63. 
Synallaxis albescens albic/ularis Berlepsch & Hartert. p. 59. 
Noted from the delta region at Las Barrancas up as 
mouth of the Apure River. 
ir as the 
