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NEW YORK STATE MUSEUM 



of the Adirondack massive, which have become inliers by burial 

 under Paleozoic rocks and subsequent partial exposure by erosion, 

 so the whole Adirondack massive. .is but an outlying- portion of the 

 Canadian shield or protaxis, that once was more or less buried 

 under lower Paleozoic rocks and is now an immense inlier in them. 

 It might be well to distinguish inliers of this magnitude from the 

 smaller ones as of the first order. We shall see that the same 

 distinction can be made in regard to the other groups of inliers, 

 and indeed has been made before by Suess in regard to the 

 " horsts." 



This Adirondack inlier of the first order which lies at the south- 

 east side of the Canadian shield, has a complete counterpart in 

 another inlier of similar size and corresponding position on 

 the southwest side of the shield in the Wisconsin Precambric 

 area ("Isle Wisconsin"). We consider that the position of 

 these two inliers in regard to the Canadian shield and the 

 Great Lakes indicates a symmetry of structure that is of some im- 



