572 



BULLETIN UNITED STATES GEOLOGICAL SURVEY. 



admire the courage and perseverance vvbich tbey displayed in recon- 

 structing or repairing their nests, though these were repeatedly de- 

 stroyed. In examining scores of nests, I was rather surprised to find 

 how small a proportion were finished into the complete retort-shape, 

 even among those which lind not been disturbed. Some were little 

 more than cups, like those of the Barn Swallow, partially arched over, 

 and many were simply conical, while in other details they varied greatly 

 according to the position in which they happened to be fixed or their 

 relations to each other. The laying season in this latitude is at its 

 height during the second and third weeks in June. Probably only one 

 brood is reared each season. Young birds are on the wing by the mid- 

 dle or latter part of July. 



List of sjyeeimcns. 



COTYLE EIPAEIA, (Lm«.) Boie. 



Bank Swallow. 



In noticing the preceding species, 1 have already alluded to the pres- 

 ent as one of those of general distribution along the Line in summer, 

 breeding in colonies anywhere where the cut-banks of the rivers afford 

 suitable sites for the digging of the holes in which the nests are con- 

 structed. 



Litit of specimens. 



PEOGNE SUBIS, {Linn.) Baird 



Purple Martin. 



I was rather surprised to find Martins breeding on Turtle Mountain, 

 having observed none at Pembina. In this locality, where there are, of 

 course, no artificial conveniences for the purpose, they must nest in 

 Woodpeckers' holes and similar cavities of trees, as they do in other parts 



