LAND BIRDS. 715 
1893. These records are all based on specimens forwarded by the light 
keepers and identified by the Division of Biological Survey, Washington, 
D.C. It was found on Isle Royale as a migrant only in 1905, on September 
5, and again September 12 and later. Norman A. Wood found it abundant 
on the Charity Islands, Saginaw Bay, September 14 to October 10, 1910. 
It is by no means rare about the College (Ingham Co.), where specimens 
we taken almost every May and September. 
According to Bicknell “The song of the Gray-cheeked Thrush commences 
low and reaches its loudest, and I think its highest, part a little beyond 
half its continuance. It is throughout much fainter and of less forcible 
delivery than the song of the Olive-backed species” (Auk, I, 1884, 130). 
The nest and eggs of the Gray-cheeked Thrush (not likely to be found 
in Michigan) are not distinguishable with certainty from’ those of the 
Olive-back. The nest is placed in low bushes or trees (rarely on the ground), 
and the eggs are greenish-blue, spotted with rusty brown, and average 
92 by .67 inches. The ground color is said to be of a decidedly deeper 
blue than in the Olive-back. 
TECHNICAL DESCRIPTION. 
Adult: Upper parts uniform olive-brown from top of head to tip of tail; sides of head 
grayish, and without any well marked eye-ring; throat and belly white, the former often 
tinged with buff; sides of throat. and entire breast with arrow-shaped spots of brown 
and black. Sexes alike in size and color. 
Length 7 to 7.75 inches; wing 3.75 to 4.40; tail 2.95 to 3.40. 
322. Olive-backed Thrush. Hylocichla ustulata swainsonii (J7'schudi). 
(758a) 
Synonyms: Swainson’s Thrush, Swamp Robin.—Turdus swainsoni, Tschudi, 1845 
and most authors until 1877.—Turdus ustulatus swainsoni, Ridgw., 1877.—Hylocichla 
ustulata swainsoni, Ridgw., 1880, and most recent authors. 
Entire upper surface clear olive, as in the Gray-cheeked Thrush, but 
a distinct buffy eye-ring and the cheeks not gray but buff. The throat 
and chest are also much more buffy than in the Gray-cheeked Thrush. 
Distribution.—Eastern North America and westward to the Upper 
Columbia River and Hast Humboldt Mountains, straggling to the Pacific 
coast. Southward in winter to Cuba, Guatemala, Nicaragua, Columbia, 
Ecuador and Peru. Breeds in the northern Alleghanies, the Catskills, 
the mountainous parts of southern New England, southern Sierra Nevada 
and northward. 
The Olive-backed Thrush is a much more common migrant in Michigan 
than the preceding species. It arrives from the south about the first 
week in May, somewhat earlier in the southern part of the state in favorable 
seasons, and much later, even the last week of May, in the Upper Peninsula. 
Thrushes are among the birds most frequently killed at lighthouses and 
there are scores of records for the present species from the Michigan lights. 
The earliest spring record is from Spectacle Reef Light, May 10, 1888, and 
the only record from Detroit River Light is May 15, 1886. The numerous 
spring records from Spectacle Reef are mostly included between May 20 
and June 1, but there is a single record of May 17, 1885, and one of June 
2, 1889. Fall records from the same Light range from September 9, 
1894 to October 20 of the same year, but the majority of records fall be- 
tween September 20 and October 10. The records at Big Sable Light, 
