COUES OX BIRDS OF DAKOTA AND MONTANA. 



571 



List of specimens. 



TACHYCmETA BICOLOK, (7/e;7/.) Cab. 



WniTE-BELLTED SWALLOW. 



Ouly observed at Pembina, where it was breeding in small numbers 

 about the Fort, together with large colonies of Cliff Swallows. 



List of specimens. 



TACHYCINETA THALASSINA, (Sw.) Cab. 



Violet- GREEN Swallow. 



Observed on one occasion (Juno 2G, 1874) on the Upper Missouri 

 near Quaking Ash River. 



PETROCHELIDON LUXIFRONS, (Say) Scl. 



Cliff Swallow. 



This is the most abundant, generally distributed, and characteristic 

 species of the family throughout the region under consideration. The 

 various streams that cut their devious ways through the prairie afford an 

 endless succession of steep banks exactly suited to its wants during the 

 nesting-season, and at various places great clusters cf the curious bottle- 

 nosed mud-nests were found, while the floaks of Swallows which often 

 hung about our camps were mainly composed of this species. At some 

 points, the Bank Swallows were breeding with them ; the some banks be- 

 ing peppered with their little round holes, generally in the soft soil just 

 below the surface, while the projecting nests of the Cliff' Swallows studded 

 the harder or rocky exposures below. At Fort Pembina, the Cliff Swal- 

 lows were so numerous as to become a nuisance ; their incessant twit- 

 tering was considered a bore, while the litter they brought and their 

 droppings resulted in a sad breach of military decorum. Nevertheless, 

 it was found almost impossible to dislodge them, and one could not but 



