BULLETIN 611 PLATE XVII 
U. &, GEOLOGICAL SURVEY 
SILVER BOW CANYON, MONT. 
Recent gorge cut by Silver Bow Creek, which was forced to take this course by the filling of its old valley to the north by lake sediments, Cliff of red lava (rhyolite) on the right. Photograph by 
Butte Photo View Co., Butte, Mont. 
