154 
BARTRAM’S YIREO. 
There is a greater difference as to colour between the sexes of this species 
than between those of the Red-eyed. The female is generally much less 
pure in its tints, while the males have usually much more of a yellowish 
tint on their upper and under plumage than is observed in the same sex of 
the other species. 
Vireo Bartramii, Swains., Bartram’s Greenlet, Swains, and Rich. F. Bor. Amer., 
vol. ii. p. 235. 
Bartram’s Yireo, Vireo Bartramii , Aud. Orn. Biog., vol. v. p. 296. 
Adult Male. 
Bill of moderate length, strong, rather broader than high at the base, 
compressed toward the end ; upper mandible with the dorsal line descending 
and slightly convex, the tip very narrow, acute, declinate, the ridge very 
narrow, the sides a little convex, the edges sharp, overlapping, with a slight 
notch close to the tip ; lower mandible with the angle of moderate length 
and rather narrowed, the dorsal line ascending and slightly convex, the back 
narrow, the sides convex, the edges inclinate, the tip acute and ascending. 
Nostrils basal, oblong, operculate. 
Head rather large, ovate ; neck short ; body rather stout. Feet of ordi- 
nary length ; tarsus compressed, with seven anterior broad scutella, edged 
behind ; toes slender, the first strong, the second much shorter than the fourth ; 
claws rather stout, much curved, compressed, laterally grooved, acute. 
Plumage soft and blended. Wings of moderate length, the first quill a 
twelfth and a half shorter than the fifth, three-twelfths shorter than the 
second, which is equal to the third, and exceeds the fourth only by a quarter 
of a twelfth. Tail rather long, nearly even, the lateral and middle feathers 
equal, and one-twelfth shorter than the longest. 
Bill brown above, pale bluish-grey beneath. Feet bluish-grey. The 
general colour of the plumage above is light yellowish-olive, the crown of 
the head deep grey, bordered on each side by a line of blackish, below which 
is a line of yellowish-white passing from the nostril over the eye, the loral 
space dusky. Quills brown, yellowish-olive on the outer margin, whitish 
on the inner. Tail wood-brown, margined with paler. The lower parts are 
white, the breast tinged with pale yellow, the throat and sides with grey. 
Length to end of tail 4-g- inches ; extent of wings 73 ; bill along the ridge 
t 6 2 , along the edge of lower mandible || ; wing from flexure 2 r 9 g ; tail 2 T | ; 
tarsus t 8 2 ; hind toe its claw ff- ; middle toe -f|, its claw . 
This species is almost exactly similar to Vireo olivaceus in colour, but is 
considerably smaller, and differs in having the wings shorter, with the first 
quill considerably shorter than the fifth, whereas in that species it is always 
much longer, generally exceeding even the fourth. 
