Tin: L\UU|-,NT[AN. 37 



Cretaceous and Eocene, and gradually diminishing to the glacial 

 age, between which and the modern there seems to have been a 

 warm period of short duration, evidenced in the deposition of mam- 

 moth bones, &c., on the Arctic coasts. The cycles of cold and warm 

 climate thus indicated in the Arctic region have, I think, an important 

 bearing on the succession of life further south, at least in Eastern 

 America, and their correlation with the climatal changes in Europe 

 would be a subject of much interest, on which, however, I do not 

 feci in a position to speak positively; but I imagine that the warm 

 and cold periods will be found to correspond with those of the Arctic 

 basin and of America. 



A leading element in the importance of the Geology of the Acadian 

 Provinces consists in that diversity from the deposits of the internal 

 plateau of Central Canada and the interior of the United States, which 

 is apparent in so many of their formations, and to which I have 

 alluded above. We are taught in this connexion the necessity in 

 any system of geological classification of distinguishing the con- 

 tinental plateaus, the lines of great foldings and of igneous action, 

 and the ancient ocean-margins from each other, and of adapting our 

 arrangements and nomenclature to their actual diversity. In order 

 to do thi.s, while adopting common designations for the great ages 

 of geological time, and for those .systems of formations which mark 

 the successive submergences and emergences of the continental 

 plateaus, separate classifications must exist for the different kinds of 

 areas, in their details. It is also, I think, necessary that we should 

 not tie ourselves down to hard-and-fast lines either as to the limits of 

 systems or as to the relative values of their divisions in widely 

 separated localities, as these differ in nature, and nothing is to be 

 gained by conventional arrangements overlooking these differences. 



Januarij 1891. 



