University of California . 



[Vol. 3. 



debris in which scratched stones are quite common. This resem- 

 bles the eroded ground moraine of the so-called Intermediate 

 glacial deposits near the head of the South Fork of Salmon 

 River.* The canon subsequently eroded in hard slates and 

 greenstone also points to the "Intermediate stage" of glaciation 

 as the age of these deposits. 



Immediately northwest of the summit of Orleans Mountain 

 (altitude 6,500 feet) there is a shallow basin about one-half 

 mile long and one-fourth mile wide, whose smooth floor and 

 hummocky sides make it evident that it was once the gathering- 

 ground of a glacier. It is drained northward into Butler Creek 

 and it is also evident that the main glacier descended along the 

 Butler Creek Valley. On the northwest this glacial basin is 

 separated from the basin of Pearch Creek by a low, undulating 

 tract (hardly a ridge), whose hummocks are composed of black 

 slate rounded by glacial action into roches moutonnees and partly 

 covered by a sheet of glacial debris. The head of Pearch Creek 

 Valley is extremely abrupt, being, in fact, a precipitous wall of 

 nearly bare black slate, several thousand feet high. The glaciated 

 tract just mentioned ends abruptly at the brow of this profound 

 declivity, and beyond doubt glacial material, and even ice itself, 

 plunged down into the valley of Pearch Creek. At one place it 

 appears to me that I can trace down over the slope a strip where 

 the black slate was smoothed by glacial action, and doubtlessly this 

 connects with the narrow strips of glacial material which extend 

 far down Pearch Creek. Curiously, with the exception of the 

 narrow strips of glacial debris which one often encounters upon 

 climbing several hundred feet above the creek, the basin of 

 Pearch Creek is singularly free from the usual evidences of 

 glaciation, there being no flats, no meadows, no lakes, no 

 distinct smoothed rock surfaces (with the exception mentioned 

 above), no lines of perched erratics, and no distinct moraines. 

 All we have to prove glaciation are remnants of as typical a 

 glacial till as any glaciated area affords — a till more than 

 usually abundantly supplied with striated rock fragments. 



*' ' The Kelation Between Certain Kiver Terraces and the Glacial 

 Series in Northwestern California." Journal of Geology, Vol. XI, No. 

 5, July-Angust, 1903. 



