Cassin’s Vireo 435 
Genus LANIVIREO. 
Medium-sized Vireos resembling Vireosylva, but with a relatively 
shorter and stouter bill, the depth of which at the base is far more 
than half the distance from the nostrils to the tip; wings as in Vireo- 
sylva, but with two conspicuous wing-bars. 
This genus, containing three species, ranges over temperate North 
America, south to Colombia (for key, see p.431). 
Cassin’s Vireo. Lanivireo solitarius cassini. 
A.0.U. Checklist no 629a—Colorado Records—Ridgway 79, p. 228 ; 
H.G.Smith 96, p.76; 08,p.189; Cooke 97, pp.112, 168; Cary 09, p.183. 
Description.—Male—Top and sides of the head dark ashy-grey, 
passing into olive-green on the back and rump; w white ring round 
the eye, continued forward over the lores ; wings and tail dusky, edged 
with olive-yellow ; the innermost secondaries with almost white, and 
the middle and greater coverts with pale yellow tips, forming a 
double wing-bar; below white, becoming pale olive-yellow on the 
flanks ; inner webs of wing- and tail-feathers edged with white ; iris 
brown, bill greyish with a darker tip, legs dusky. Length 4-90; wing 
2-90; tail 2-15; culmen -42; tarsus -70. 
The sexes are practically alike ; the young birds have the orbital 
ring and the under-parts tinged with brownish-buff. 
Distribution.—Breeding in western North America from British 
Columbia to southern California, eastwards on migration through 
Arizona and New Mexico, and south through Mexico to Oaxaca. 
Cassin’s Vireo is of accidental occurrence in Colorado. It was 
represented in the Maxwell collection (Ridgway), and has since been 
obtained on three occasions near Denver by H. G. Smith—a male on 
the Platte River, September 16th, 1884, another example at Cresswell 
in Jefferson co. on September 9th, 1887, and a female on Coal Creek 
on May 13th, 1888; it was also taken by W. F. Doertenbach near 
Pueblo September 6th, 1897 (Cooke), and Cary has recently obtained an 
example on September 4th on the Escalante hills in western Routt co. 
Plumbeous Vireo. Lanivireo solitarius plumbeus. 
A.O.U. Checklist no 629b—Colorado Records—Allen 72, pp. 149, 
156 ; Aiken 72, p. 198 ; Trippe 74, p. 100 ; Henshaw 75, p. 224 ; Minot 
80, p. 229; Tresz 81, p. 289; Allen & Brewster 83, p. 160; Drew 85, 
p. 15 ; Beckham 835, p. 141 ; Kellogg 90, p. 90 ; Lowe 94, p. 269 ; Cooke 
97, pp. 19, 112, 218 ; Henderson 03, p. 236 ; 09, p. 239. 
Description.—Male—General colour above slaty-grey, with a very 
faint tinge of olive on the rump; orbital ring and supra-loral stripe 
white, slightly separated by a black spot in front of the eye; wings 
and tail dusky black edged with white, especially the outer tail-feathers 
EE 2 
