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 

 chStiry, chetiry, che&ry, ehSHry, decreasing in tone to a quite 

 faint lisp; then, after a short pause, the notes, cheou 'twit,, 

 tritter, 'fritter, are uttered ; and the whole is finished usually 

 with the ejaculation, chickwheu. 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. 



TUEDUS SWAINSONII.— Cabanis. 



The Olive-backed Thrush; Swainson's Thrush. 



Tvrdus Swainsonii. Cab. in Tschudi F. Peruana (1844-46) 188. 

 Tardus sulitarius, 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; 



