ART. XXV -FIELD-NOTES ON BIRDS OBSERVED IN DAKOTA 

 AND MONTANA ALONG THE FORTY-NINTH PARALLEL 

 DURING THE SEASONS OF 1873 AND 1874.* 



By De. Elliott Coues, U. S. A., 



Late Surgeon and Xatui'alist U. S. Xorthern Boundary Comniission. 



The following notes result from observations made in the field during 

 my connection with the United States Northern Boundary Commission — 

 Archibald Campbell, Esq., Commissioner, Major W. J. Twining, Corps of 

 Engineers, U. S. A., Chief Astronomer. The line surveyed by the Com- 

 mission in 1873 and 1874 extended from the Eed Eiver of the Nortli 

 to the Eocky Mountains, a distance of 850 miles, along the northern 

 border of the Territories of Dakota and Montana, in latitude 49° north. 

 During the season of 1873, I took the field at Pembina, on the Eed 

 Eiver, early in June, and in the course of the summer passed along the 

 Line nearly to the Coteau de Missouri, returning from the Souris or 

 Mouse Eiver via Fort Stevenson and the Missouri to Bismarck. This 

 season's operations w^ere entirely on the parallel of 49<^, and in the water- 

 shed of the Mouse and Eed Elvers, my principal collecting-grounds 

 being Pembina, Turtle Mountain, and the Mouse Eiver. This region 

 of the northerly waters is sharply distinguished geographically and 

 topographically, as well as zoologically, from the Missouri and Milk Eiver 

 Basin, which I entered the following year. In 1874, 1 began at Fort 

 Buford, at the moutli of the Yellowstone, travelled northwesterly to 49o, 

 which was reached at Frenchman's Eiver, one of the numerous tribu- 

 taries of Milk Eiver, and thence along the parallel to the Eocky Mount- 

 ains at Waterton or Chief Mountain Lake and other headwaters of 

 the Saskatchewan ; returning back on the Line to Three Euttes or Sweet- 

 grass Hills, thence direct to Fort Benton, Montana, and thence by a boat 

 voyage down the Missouri to Bismarck. In neither season was much 

 collecting done except along the parallel itself; and the operations of 

 each season were in a region sharply distinguished, as I have said, by 

 its faunal peculiarities. From these two broad belts of countrVj cor- 

 responding at 490 nearly to the Territories of Dakota and Montana 

 respectively, is to be set apart a third, that of the Eocky Mountains 

 alone. 



I made an elaborate comparison of the faunal characters of these three 



[*For articles on other portions of the same writer's collection, see this Bulletin, 

 this V0I.3 No. 1, pp. 259-292, and No. 2, pp. 481-518.— Ed.] 



Bull. iv. No. 3 1 545 



