190 



Kilometres. limestone. The steeply dipping beds on the 

 west of this creek belong to the Sawback 

 formation. This formation lies conformably 

 under the Devonian Intermediate limestone, 

 but the exact age is still doubtful, as no fossils 

 have yet been found in it. Lithologically, 

 a part of this series resembles the rocks of 

 Silurian age in the Beaverfoot range to the 

 west. To the south of the railway is the valley 

 of Healy creek which extends to Simpson 

 pass, and is the course followed en route to 

 Mt. Assiniboine, the Matterhorn of the Can- 

 adian Rocky mountains. Bow river has here 

 a meandering course, some of the lobes having 

 been cut through, to form oxbow lakes. 

 88 m. Sawback. — Alt. 4537 ft. (1,384 m.). West 



140-8 km.of Banff the railway crosses the strike of the 

 formations in the Vermilion Lake and Sawback 

 ranges, but at this point the valley of the 

 Bow turns sharply to the northwest and follows 

 along the strike of the formations as far as 

 Laggan. The Carboniferous limestones dip at 

 about 65 to the southwest, so that smooth 

 cliffs formed along the bedding-planes are 

 characteristic of the Sawback range. Mt. 

 Hole-in-the-Wall, to the north of the station, 

 is so called because it contains in its side a 

 cavernous opening. This cave at its outer 

 end is 50 feet (15 m.) in diameter, but becomes 

 smaller behind as the floor rises. It is about 

 150 feet (46 m.) long and is situated, 1,500 feet 

 (458 m.) above the railway, in the Lower 

 Banff limestone. The position of the Lower 

 and Upper Banff shales is always readily 

 recognized by a depression on the surface. 

 93 m. Massive — Alt. 4,600 ft. (1,402 m.). On 



148-8 km. the south side of Bow valley, Pilot mountain 

 towers 5,000 feet (1,513 m.) above the railway. 

 The base consists of Devonian limestone, and 

 the peak is capped by Upper Carboniferous. 

 From the Intermediate limestone in Fossil 

 mountain, 10 miles northeast of Laggan, the 

 following Upper Devonian fauna have been 

 determined : — Spirifer whitneyi Hall ; Productella 



