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U. S. P. E. R. EXP. AND SURVEYS — ZOOLOGY — GENERAL REPORT. 
with yellow ; beneath pale, variegated with black. Tail rufous. Rump rufous yellow, with 
transverse brown bands. Wings sparsely dotted. Breast white, with transverse bands of 
black. Length to the rump, 3£ inches ; tail, 2 inches 1 lines ; wing, 3 inches 5 lines. Kodiak." 
The Tardus aonalaschka of Gmelin, based on a bird the " size of a lark, crown and back brown, 
marked with obscure dusky spots ; breast yellow, spotted with black ; wing coverts, prime 
quills, and tail dusky, edged with testaceous ; hab. Aonalaschka, cabinet of Sir Joseph Banks," 
of Latham and Pennant might possibly refer to a young bird of the present species ; but in the 
entire uncertainty in the case, and the possibility of their having some one of the similarly 
colored American sparrows before them, it may be best to retain Mr. Audubon's name. 
SYNOPSIS OF SUB-GENERA AND SPECIES. 
Turdus. — Tarsi elongated, considerably longer than the middle toe ; the scutellae not 
distinguishable. Tail feathers acuminate. Bill distinctly notched. Above plain olive or 
reddish, beneath white ; the breast spotted. 
Rufous brown above, much brightest towards the head, becoming olivaceous on the tail ; 
pure white beneath, thickly spotted on the whole breast and sides with blackish. 
mustelinus. 
Yellowish olive above, becoming decidedly rufous on the rump and tail. Beneath white, 
scarcely more yellow anteriorly ; breast with well defined spots like the back. Tibiae 
and sides yellowish olive brown .pallasii. 
Similar to the last, but smaller ; the under parts purer white ; the tibiae and sides 
grayish olive brown nanus. 
Similar to pallasii, but larger ; the back greenish, not yellow olive, passing into reddish 
on the tail silens. 
Above uniform yellowish red ; throat and jugulum decidedly yellowish, the latter with 
very obsolete spots fuscescens. 
Similar to the last, but more yellow olivaceous above, and the jugulum distinctly marked 
with spots like the back ustulatus. 
Above greenish olive, not appreciably lighter on the tail. Sides of the head with the 
breast and throat strongly tinged with reddish yellow, and a ring of the same round 
the eye. Breast with very distinct spots of dark brown sioainsonii. 
Above greenish olive, not appreciably lighter on the tail. Sides of the head ashy ; ring 
round the eye, with the throat, and breast white. Breast with very distinct spots 
of dark brown, almost black aliciae. 
Planisticus. — Body stout ; tarsi not much longer than the middle toe, the scutellae somewhat 
visible on the inside below. Tail feathers rather truncate. Bill distinctly notched. Above 
plain olive ; throat and chin alone white, streaked with black ; breast rufous. 
Above grayish olive ; top of head and the tail blackish. Beneath reddish brown ; the 
anal region and crissum, with eyelids, white migratorius. 
Ixoreus. — Bill slender, elongated, nearly as long as the head ; commissure curved ; tip 
without any notch. Scutellae not distinguishable. Claws larger than in Planisticus. First 
primary about one-fourth the longest. Tail feathers acuminate. Throat and under parts 
entirely unspotted. 
Above dark plumbeous ; beneath reddish brown, with a pectoral band of black ; wings 
varied with reddish brown, and a stripe of the same behind the eye naevius. 
