61 i BULLETIN UNITED STATES GEOLOGICAL SUEVEY. 



OH.ETURA PBLAGIOA, (Linn.) Bd. 



Chimney Swift. 



Common at Pembina, and traced thence westward only to the Mouse 

 Eiver. Kot seen in the Missouri region nor in the Eocky Mountains. I 

 did not notice where the birds were breeding; but from the circumstance 

 of seeing them habitually flying about over the timber of the river bot- 

 tom, instead of at the fort, I judge that they here still retained their 

 primitive custom of nesting in hollow trees. 



List of specimens. 



TEOCHILUS COLUBRIS, Linn. 



KUBY-THROATED HUMMINGBIED. 



Quite common at Pembina, in the open flowery glades of the woods 

 along the river. Not seen west of this point. 



List of specimens. 



SELASPHORUS RUFUS, {Qm.) Sw. 



Rufous Hummingbird. 



Found in considerable numbers at our camp on Chief Mountain Lake, 

 in open flowery spots amongst the windfalls, at an altitudeof about 4,200 

 feet. 



List of specimens. 



