5i 



and the more resistant gneisses, upon which the river 

 has been held, while it has excavated the deep gorge 

 in the shales below. Continuing along the inner edge of 

 the Micmac terrace to Chateau Richer, the railway passes 

 in sight of quarries on the face of the bluff where limestone 

 instead of shales are exposed. Clearly the bluff has been 

 trimmed back into the coast without regard for the strike 

 or the dip of the rocks. Beyond here the terrace broadens 

 and runs uninterruptedly for many miles. 



Two facts about this Micmac shore line are pre-eminent 

 in importance. First, its strength, in view of the narrow 

 limits within which waves could develop between the 

 Island of Orleans and the north shore, is extraordinary. 

 It has been cut back as far into the coast as the distance 

 across the shelf, — or over half a mile. Secondly, the alti- 

 tude of the shelf here near Quebec is almost exactly the 

 same as its altitude 300 miles (480 km.) down the estuary; 

 and in the interval there are no signs of local warping. 

 This recent emergence of the coast of the lower St. Law- 

 rence within the limits stated was a perfectly uniform 

 uplift. 



A study of the flora of the Micmac terrace at Ste. Anne 

 de Beaupre shows a striking intermingling along the high 

 tide zone of salt marsh plants and fresh water plants. 

 This might be interpreted to mean that the fresh marsh 

 is gaining on the salt, and that the plants from the inner 

 marsh are advancing out over the tide marsh as fast as 

 the coast rises. On the other hand, it might be interpreted 

 to mean that the salt marsh plants are invading what was 

 formerly fresh marsh, during a slow subsiding of the coast. 

 And finally, it is possible to regard the intermingling 

 of the two flora as the result of the varying effects of high 

 tides and seasons of heavy rainfall, which now flood the 

 marsh with salt or brackish water and then fill it tempo- 

 rarily with fresh. So far as can yet be discovered, there 

 is no way to demonstrate whether the Micmac shelf 

 is still slowly emerging from the sea, or is stationary, or 

 is slowly subsiding. In general recently collected facts 

 from the New Brunswick and New England coast favour 

 the idea that no change of level has occurred during the 

 last few thousand years. 



35063— 4I 



