DALY: PHYSIOGRAPHY OF ACADIA. 83 



duced to a lowland throughout a whole physiographic province. We 

 expect, therefore, that if the upland facet of the Southern Plateau be 

 of the nature of a true peneplain, it must have once extended far aud 

 wide over Acadia. It ueed not now be continuous, for the warping, 

 which we believe has occurred, may be expected to have revived the old 

 rivers of the former cycle, and to have developed new subsequent 

 drainage in the present cycle ; that, therefore, belts of lowland may be 

 looked for wherever weak rocks appear. This deduction is realized in 

 the facts. Where, for example, the older, harder Palaeozoics appear out- 

 side of the Southern Plateau, there uplands and fragments of the pene- 

 plain are found to occur, and it is the soft Carboniferous and Triassic 

 sediments that underlie the extensive lowlands. In fact, the various 

 topographic divisions of Acadia from the Southern Plateau to Gaspe are 

 perhaps best described in terms of this facet. The evidences for this 

 statement will be more clear after a brief recital of the facts relating to 

 each of the divisions. Since I have had the opportunity of making 

 but one excursion and that by railway, across Cape Breton Island, and 

 since the amount of information regarding the recent geological history 

 of that island is scanty, I shall not attempt to speak of it in detail. 

 From the nature of its terranes and from its geographical position, it 

 ought to include part of the peneplain ; and, indeed, from the descrip- 

 tions of Campbell 1 and Fletcher ('84, p. 77), it would seem that the facet 

 is excellently represented in the northern half of the island. 



The Cobequid Plateau. — The Cobequid mountain belt runs nearly 

 due east aud west along a major axis about seventy-five miles long ; 

 its average and fairly constant width is from nine to ten miles. The 

 opinion of the Canadian Survey officers has varied with respect to 

 the age of the rocks composing these old mountains. According to 

 the map issued by the Selwyn survey in 1886, they are pre-Cambrian, 

 but Ells ('97, p. 119) has recently expressed the conclusion that 

 they " may with propriety be regarded as more recent than the pre- 

 Cambrian," and this is true of the granite intrusions at least, which are 

 late Devonian or post-Devonian. In any case, however, we know that 

 the Yange is composed of highly crystalline, complexly folded series of 

 rocks that are now bounded by a rolling plateau-top from eight hun- 

 dred to one thousand feet above the sea, some "peaks " reaching eleven 

 hundred feet in altitude (Chalmers, '95, p. 9). The general surface 

 of this plateau now stands at an elevation which correlates it well with 

 the peneplain of the Southern Plateau. The extension of the latter facet 

 1 Dawson, Acadian Geology, 2nd ed , pp. 564, 685. 



