COUES ON BIEDS OF DAKOTA AND MONTANA. 



551 



thick, giving a bulky, irregular, and rather slovenly appearance, and 

 causing the cavity to appear comparatively small, — it was only about 

 2J inches in diameter by less than 2 inches in depth, though the whole 

 nest was as large as a child's head. 



List of ftjH'cimens. 



MIMUS CAROLINEIsTSIS, {Linn.) Gray. 

 Catbird. 



The Catbird was ascertained to be one of the common species of the 

 Red River region, where it was breeding in June, in situations similar 

 to those it selects in the East. 1 traced it westward to Turtle Mountain, 

 but did not observe it again in the Rocky Mountains, where its presence 

 was to have been expected. It is also a rather common species on the 

 Upper Missouri and the northern affluents of this and of the Milk River. 

 The Missouri appears to be the highway by which the species gains the 

 Rocky Mountains, as observed by Dr. Hayden. The naturalists of the 

 Northwest Boundary Commission collected specimens in Washington 

 Territory, and Sir John Richardson has left a record of its occurrence 

 in the Saskatchewan region as far north as latitude 54P north. As at 

 Pembina, the bird was breeding in June in the shrubbery along the 

 Upper Missouri and its tributaries. 



List of specimens. 



HARPORHYis^CHUS RUFUS, {Linn,) Cab. 

 Thrasher, or Brown Thrush. 



Observed at Pembina, which appears to be near the northern limit of 

 the distribution of this species. In other latitudes, however, it extends 



