DEVONIAN. 333 



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M 11. ROCKY MOUNTAINS OF BRITISH COLUMBIA. 



In the eastern range of the Rocky Mountains, at the gap of Bow River, Alberta, 

 Ordovician strata are followed with apparent conformity by a quartzite succeeded 

 by dolomites of Devonian age. These strata do not occur in the western range, 

 where the "Halysites beds" (Silurian) are present. McConnelP^'" describes the 

 Devonian ("Intermediate limestone") as follows: 



The Intermediate limestone underlies the BanflF Hmestone conformably, and passage beds 

 partaking of the lithological character of both groups occur at the junction of the formations. 

 It is mainly composed of a great series of brownish dolomitic limestones and has a thickness of 

 about 1,500 feet. The typical dolomites of this formation are dark brownish in color, are finely 

 crystalline, and are often irregularly hardened by concretionary action. They have, in many 

 places, a blotched appearance, due to small cavities becoming filled with calc spar, are cherty, 

 and are characterized throughout by an abundance of corals. In some sections a hght-grayish 

 variety is not infrequent. It is more coarsely crystaUine than the dark variety and is unfos- 

 siHferous. In addition to the dolomites, beds and bands of sandstone, quartzite, and calcareous 

 limestone are found aU through the series. A light-yellowish siliceous band, varying in thick- 

 ness from 100 to 400 feet, occurs near its base, on the south fork of Ghost Kiver and along the 

 eastern part of Devil's Lake valley, and is also found at the entrance to the White Man's Pass. 



A good section across this series was obtained in the first range, near the Gap of the Bow. 

 Here it dips to the west, at an angle of 40°, and is inclosed between the Castle Mountain and 

 Banff Hmestones. The former, at this point, is terminated above by some shaly nondolomitic 

 limestone, overlying which is about 40 feet of reddish and bright-yeUowish weathering sand- 

 stones and quartzites, forming the base of the intermediate formation. Above these come 

 several hundred feet of brownish-weathering, irregularly hardened magnesian hmestone, holding 

 cherts and corals, succeeded by hght-colored, regularly bedded crystaUine dolomites. The 

 latter grade upward into a series of alternating beds of the two last varieties, associated with 

 some beds of quartzite. Then comes a small band, consisting of soft greenish crumbling argil- 

 laceous sandstone, and hard yellowish-weathering quartzites, overlying which are 20 feet of 

 grayish limestone. This limestone is succeeded by magnesian limestones and quartzites, above 

 which come 50 feet of heavily bedded brownish-weathering dolomites, for min g the top of the 

 series and underlying the bluish massive beds of the Banff hmestone. This section affords a 

 fair general illustration of the relative lithological importance of the different members of the 

 series, but could not be even approximately duphcated half a mile away, owing to differences 

 in local detail. 



The fossUs of the Intermediate limestone are usually badly preserved and consist mainly 

 of almost structureless corals. 



M 19. NORTHERN NEW BRUNSWICK. 



A small area of Eo-Devonian is shown on the map at the west end of Chaleur Bay. 

 The rocks are red sandstone and gray shale associated with intrusive traps and 

 with gray and purple feldspathic ash rocks. Coarse sandstones and conglomerates 

 occur and carry Devonian plant remains.'"® 



On the Restigouche, at the western extremity of Chaleur Bay, occurs a small 

 area of Devonian strata which have afforded an interesting fish fauna and some 

 plant remains. Whiteaves ^ narrates the early discoveries and simimarizes the 

 facts as follows : 



The first of these discoveries led to further investigations by officers of the Canadian Sur- 

 vey in 1880, 1881, and 1882, which revealed the existence of a remarkable assemblage of fossil 



