252 Annals of the Carnegie Museum. 



From Spring Canon in the Ruby Mountains a large collection of Car- 

 boniferous fossils was obtained. A trip of a few days was then made 

 to "Old Baldy Mountain," south of Virginia City, where collections 

 were obtained from many horizons in a large series of Carboniferous 

 limestones and shales which occur there. 



In the latter part of September Mr. Raymond returned to Pitts- 

 burgh, while the writer prepared for a trip to Idaho. 



From Ruby to Monida, Montana. 



Ascending the Ruby River I passed through the lower canon, where 

 the Ruby cuts through Arch^an gneisses and crystalline limestones, to 

 the middle valley of the Ruby River. In the lower portion of this 

 valley and continuing some distance up the Sweetwater to the 

 southwestward are considerable exposures of Lower White River de- 

 posits, while overlying these on the east side of the river, and farther 

 up on the west side reaching far up on the flanks of the Crazy Moun- 

 tains, are late Miocene sands and gravels. Both formations are very 

 sparingly fossiliferous, though enough teeth and bones of mammals 

 have been found to determine approximately the age of the deposits. 

 I ascended the Ruby River to where Ledford Creek enters from the 

 northwest. This stream issues from canons in the northern portion 

 of the Snow Crest range, and then flows through a long narrow grassy- 

 bottomed valley, carved through Miocene sands and gravels. Nearly 

 the whole of the Middle Ruby A^alley, in fact, is composed of Ter- 

 tiary deposits, dissected by many streams and ravines and rising 

 higher and higher toward the elevated narrow ridge of the Snow Crest 

 Range, covering all but the higher portions in its thick mantle of 

 sand and gravel. The road up Ledford Creek ascends quite rapidly, 

 but the benches rise with it. My plan was to ascend this creek, and 

 then, if possible, make my way near the foot of the mountains south- 

 westward to one of the branches of Blacktail Deer Creek, thus get- 

 ting a view of a portion of the country which I had not previously 

 examined ; but I had not yet been able to ascertain whether the 

 route was practicable with team and wagon. I stopped at a house to 

 inquire the way and was fortunate enough to obtain the services of a 

 boy to guide me over the most difficult portion of the way, where there 

 was no trail, to a road which goes to Dillon ; but after ascending a 

 long steep grade, I missed the dim trail, which I should have taken, 

 and lost my way among the foot-hills. Turning off the road I as- 



