550 BULLETIN UNITED STATES GEOLOGICAL SURVEY. 



List of specimens. 



TURDUS (HYLOOICHLA) SWAINSOM, Cah. 



Olive -BACKED Thrush. 



The remarks made under head of the last species, with regard to 

 geographical distribution, are equally applicable to the present one. It 

 was only observed, however, in September, during the general autumnal 

 migration, in tlie slight fringe of trees along the stream where I was 

 collecting at the time. In a country so nearly treeless as is the tract 

 lying between the Eed Eiver and the Kocky Mountains, the slightest 

 pieces of woodland are eagerly sought by all the migrants as stoppiug- 

 placfiS for food and rest. Though at other seasons tenanted by few 

 species, they become populous in the fall by the presence of great 

 numbers of small insectivorous and granivorous species, among which 

 the Turdidce^ Sylricolidce, and Fringillidce are conspicuous. 



List of specimens. 



TUEDUS (HYLOOICHLA) FUSCESCENS, 8U^lu 



Veert, or Wilson's Thrush. 



Unlike either of the preceding species, the Yeery does not appear to 

 extend westward beyond the Valley of the Eed Eiver, — at any rate, it 

 was only observed in the vicinity of Pembina. Here it was found 

 breeding in abundance during the month of June, when its exquisite 

 song enlivened the tangled recesses of the wooded river-bottom, in 

 which the timid birds secreted themselves, and formed one of the most 

 characteristic pieces of bird-melody to be heard in that ill-favored 

 locality. A nest was found on the 9th of June, containing four fresh 

 eggs, uniform, bluish-green in color, and measuring about 0.86 in length 

 by 0.66 in diameter. It was placed upon a small heap of decayed leaves 

 which had been caught on the foot-stalks of a bush a few inches from 

 the ground, and composed of w^ eed -stems, grasses, and fibrous bark- 

 strips, woven together, and mixed with withered leaves. The walls were 



