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152 ORNITHOLOGY AND OOLOGY. 
about .90 by .66 inch. As in many other eggs, the longest 
specimens are not always the broadest. The following are 
the dimensions of four eggs, taken at random from a large 
number of this species: .92 by .64 inch, .88 by .64 inch, 
.86 by .66 inch, .87 by .67 inch. 
From the first arrival of this bird, during its whole stay 
here, it seems to prefer the neighborhood of a swampy wood 
for its home. ‘There, during the mating and incubating 
seasons, the notes of the male may be heard at the earliest 
hours of the morning and evening; and, in cloudy weather, 
through the day, and sometimes in the night. The song is 
a peculiar one, with a singular metallic ring, exceedingly 
difficult to. describe: it begins quite loud, the syllables 
chétiry, chétiry, chétry, chétry, decreasing in tone to a quite 
faint lisp; then, after a short pause, the notes, cheouw ’twit, 
tritter, ’tritter, are uttered ; and the whole is finished usually 
with the ejaculation, chickwhéu. This song is often re- 
peated; and sometimes two or three males, perching on a 
low shrub or tree, emulate each other in a musical contest 
that is very pleasing to hear. This thrush, as are all the 
others, is eminently insectivorous; and through the whole 
day he may be heard busily searching among the fallen 
leaves for his favorite food. 
About the 10th of September, it leaves for the South: at 
this time, like most of the others, it is silent and retiring, 
and is found only in localities that are thickly wooded with 
a growth of small birches and oaks. 
TURDUS SWAINSONII. — Cabanis. 
The Olive-backed Thrush; Swainson’s Thrush. 
Turdus Swainsonii. Cab. in Tschudi F. Peruana (1844-46) 188. 
Turdus solitarius, Wilson. Am. Orn., V. 
DESCRIPTION. 
Third quill longest, second and fourth but little shorter, and much longer than 
the fifth (by thirty-five one-hundredths of an inch); upper parts uniform olivaceous, 
with a decided shade of green; the fore part of breast, the throat, and chin, pale 
brownish-yellow; rest of lower parts white, the sides washed with brownish-olive; 
