COUES ON BIRDS OF DAKOTA AND MONTANA. 547 



onus vociferus, Ticrdus pallasi, Geothlypis Philadelphia, Goniaphea ludovi- 

 eiana, Setophaga ruticilla, and many others. ISpermophilus richardsoni 

 begins in this region, and S. fraulcUni and doubtless Onychomys end 

 here. There are Badgers in plenty and a few Antelopes; there were no 

 Buffalo in 1873, though the country was still scored with their trails, 

 and skeletons were plenty from the Mouse Eiver westward. This region 

 is still more strongly marked by the absence of the Missouri specialties. 



2. The Missouri region, or the great watershed of the Missouri and 

 Milk Elvers. As soon as we cross the Coteau, the whole aspect of the 

 €ountry changes, and there is a marked difference in the fauna. We 

 enter a much more sterile and broken region, absolutely treeless except- 

 ing along the larger water-courses, full of " bad lands", with much sage- 

 brush, — such country stretching, with scarcely any modification, to the 

 base of the Eockies. In this latitude, the Milk Eiver is the main artery, 

 with many north-south afduents crossing 49°. The characteristic mam- 

 mals are the Buffalo (first seen in 1874 in the vicinity of Frenchman's 

 Eiver), Antelope, Prairie and Sage Hares {LL. campestris and sylvaticus 

 var. nuttalli), the Prairie " Gophers" {Spermophilus richardsoni, in extra- 

 ordinary abundance), and Prairie "Dogs" {Cynomys hidovicianus), some 

 of these being perfectly distinctive of the Missouri as compared with 

 the Eed Eiver region. Putorius longicauda is the Ermine of this region. 

 Kit Foxes ( Vulpes velox) are common, but so they are along the Mouse 

 Eiver. The characteristic birds are Galamospiza hicolor, Tyranmis ver- 

 ticalis, Plectrophanes maccowni, Pica hudsonica, Speotyto hypogwa, Gentro- 

 cerctis urophasianus (diagnostic of the region, like the mammal Gynomys 

 ludovicianus, or the reptiles Phrynosoma douglassi and Grotalus confitien- 

 tus), and Eiidromias montanus. Few, if any, distinctively Eastern birds 

 extend across or even into this region. Plectrophanes ornatus goes to 

 the mountains, but in diminished numbers; one specimen of N'eocorys 

 was taken near the mountains, but neither Passerculus hairdi nor Gotur- 

 niculus lecontii was observed ; Eremophila continues in full force. 



The Sweetgrass Hills, or Three Buttes, are the most considerable out- 

 liers of the Eocky Mountains, along the parallel of 49°, quite Isolated 

 on the prairie. I noticed no avian specialties here, but Mountain Sheep 

 were comparatively abundant (as they were also along the bluffs of the 

 Missouri Eiver, above the mouth of the Yellowstone), and the Yellow- 

 haired Porcupine, Erethizon epixanthus, was numerous, 



3. Rocliy Mountain region. — Eising gradually and, of coarse, imper- 

 ceptibly, the Missouri region maintains its features to the very foot 

 of the mountains, the headwaters of the Milk Eiver being prairie 

 streams, sluggish, warm, and muddy, with much alkaline detritus. The 

 divide between this watershed and that of the Saskatchewan is too 

 slight to be recognized as such by an inexperienced eye ; on passing it, 

 we strike the clear, cold, turbulent streams from the mountains, abound- 

 ing in iSalmonidcBj and soon enter the woods. This region is strongly 

 marked, not only by " Western " species, in the geographer's sense, but 



