570 BULLETIN UNITED STATES GEOLOGICAL SURVEY. 



SETOPHAGA RUTICILLA, {Linn.) Sw. 

 Redstart. 



Yery abundant at Pembina, where it breeds. Early in June, the 

 birds exhibited the incessant activity which marks the mating season, 

 and were conspicuous in the sombre foliage of the dense timber along 

 the river, no less by the brilliancy of their black, white, and red plum- 

 age, than by their noisiness and sprightly actions. Their characteris- 

 tic habits of expanding and flirting the tail, and running sideways along 

 the twigs of trees, and their wonderful agility in the pursuit of flying 

 insects, are all particularly well displayed at this season. 



Though I did not myself observe the species further westward along 

 the Line, nor anywhere in the Missouri region, it has been traced by 

 others, especially by Dr. J. G. Cooper, along the Upper Missouri and 

 Milk Rivers, and thence to the Cceur d'Alene Mountains. It is also 

 known to occur in Colorado and Utah. 



List of specimens. 



HIRUNDO ERYTHROG ASTRA HORREORUM, {Barton,) Coues. 



Basn Swallow. 



I find no specimens of this species entered in ray register from Pembina, 

 where, according to my recollection, it was not breeding at the time of 

 my visit, though the family- was there well represented by numbers of 

 Cliff and Wbitebellied Swallows. Nevertheless, Barn Swallows were 

 commonly observed, during July and August, at various points along 

 the Line, nearly to the Rocky Mountains. Eligible breeding-places for 

 this species being few and far between in this country, it is correspond- 

 ingly uncommon, at least in comparison with its numbers in most settled 

 districts. A small colony of the birds which had located for the sum- 

 mer on a small stream west of the Sweetgrass Hills afforded me an oppor- 

 tunity of observing a curious modification of their nesting-habits, which 

 I believe had not been known until I published a note upon the subject. 

 The nests were built in little holes in the perpendicular side of a " cut- 

 bank", — whether dug by the birds themselves or not I could not satisfy 

 myself, though I am inclined to think that they were. My assistant, 

 Mr. Batty, seemed to feel quite confident in the matter; and the proba- 

 bility is, that it the holes were not wholly made by the birds, they were 

 at least fitted up for the purpose. 



