BIRDS OF NORTH AND MIDDLE AMERICA, 11 
g. Tail one and a half times as long as wing; not crested; spotted above 
in both sexes .......--...0-2 202 e eee eee Nisius (extralimital).¢ 
gg. Tail much less than one and a half times as long as wing; conspicu- 
ously crested; not spotted above (adult male wholly dusky, 
female barred with blackish and rusty). .Lochites (extralimital).> 
ee. Tail little if any longer (usually much shorter) than wing. 
J. Toes relatively shorter, the middle toe (without claw) not longer than 
distance from nostril to tip of maxilla, or else tail not more than two- 
thirds as long as wing, and wings and tail conspicuously spotted. 
g. Tail much less than two-thirds as long as wing, truncated. 
Pygiptila (extralimital). ¢ 
gg. Tail at least two-thirds as long as wing, much rounded or graduated. 
h. Tail not more than two-thirds as long as wing; bill relatively 
smaller, the distance from nostril to tip of maxilla less than 
length of middle toe without claw; wings, tail, and upper 
tail-coverts conspicuously spotted with white (adult male) or 
buffy (female).....................Megastictus (extralimital).¢@ 
hh. Tail more than two-thirds as long as wing; bill relatively larger, 
the distance from nostril to tip of maxilla greater than length 
of middle toe without claw; wings, tail, and upper tail-coverts 
with minute white or buffy spots or none at all. 
4. Plumage without spots, streaks or bars (plain brownish or 
olive above, yellowish olive below, the wings and tail rufes- 
cent; tail much shorter than wing....... Thamnistes (p. 21). 
w#. Plumage more or less spotted or streaked (adult male black 
with white dots on wing-coverts and small white tip to lateral 
rectrices, female slate color or olive, streaked with whitish; 
tail nearly as long as wing)................ Abalius (p. 24). 
Jf. Toes relatively longer, the middle toe (without claw) longer than 
distance from nostril to tip of maxilla; (tail more than two-thirds as 
long as wing). 
g. Bill relatively much larger and stronger (exposed culmen equal to 
or longer than middle toe with claw), more strongly uncinate; crest 
more conspicuously developed. 
h. Bill more compressed, its width at frontal antise much less than 
its depth at same point, and equal to less than half the distance 
from nostril to tip of maxilla; larger (total length about 200 mm.); 
under parts white, the adult male black, the female rufous- 
brown, above with more or less of white on wings. 
Taraba (p. 27). 
hh. Bill less compressed, its width at frontal antiz nearly if not quite 
equal to its depth at same point and equal to at least half the 
distance from nostril to tip of maxilla; smaller (total length not 
more than 170 mm.); under parts not white (except, sometimes, 
in part). 
@ Nisius Reichenbach, Av. Syst. Nat., 1850, pl. 71. Type, Thamnophilus leachii 
Such. (Southeastern Brazil and niorihiers Argentina; monotypic?) 
b Lochites Cabanis and Heine, Mus. Hein., ii, Aug., 1859, 18. Type, Lanius severus 
Lichtenstein. (Southeastern Brazil; mipnotypie?) 
¢ Pygiptila Sclater, Proc. Zool. Soc. Lond., 1858, 220. Type, Thamnophilus 
maculipennis Sclater. (Upper Amazons; monotypic.)—Pygoptila (emendation) 
Cabanis and Heine, Mus. Hein., ii, 1859, 15. 
@ Megastictus Ridgway, Proc. Biol. Soc. Wash., xxii, Apr. 17, 1909, 69. Type, 
Myrmeciza margaritata Sclater. (Upper Amazons; monotypic.) 
