BELT ON THE GLACIAL PERIOD IN NORTH AMERICA. 91 



broad plated "white edged orange fins, is the true analogue to the 

 Char of Europe. T\T:iilst Gloverii, in its brown colour and teeth 

 resembles Fario of Europe and Covfinis, the great lake trout of 

 Scotland's lakes. So far I have never heard of Corregonus 

 the analogue to the Vcndace of England, but may find it 

 at any time ; not so with the splended analogue to the Grayling 

 of Europe, the Signifer of Sir John Richardson. His range is too 

 northern, and his great beauty and typical dorsal would have betrayed 

 his whereabouts lonsr since. 



Art. XL The Glacial Period in North x-^merica. By 

 Thomas Belt, F. G. S. 



IRead May 8, 1866.] 



I. Introduction. IL Glaciated Piocks and Drift-Beds of Nova Scotia. 



1. Eroded, valleys and scratched rocks. 2. Drift-beds. 3. Gold in the Drift. 4. 

 3Iarine beds of the St. Laivrence. III. Origin of the Glacial Period. 1. 

 Theories of Origin. 2. Recent changes of level of the land in northern hemisphere 

 greatest towards the pole. 3. Effect of shutting off warm currents from the Polar 

 Basin. IV. Action of the Ice. 1. Statement of the question. 2. Accumula- 

 tion of the Ice. 3. Culmination. 4. Retreat. V. Application of the Theory 

 TO SOME of the PHENOMENA OF THE Drift. 1. Local character of the Drift. 



2. Trans2}ortecl£locks of Berkshire, Massachusetts. 3. Drift of the St. Lawrence. 

 Terraces and Stratified, Deposits. VI. Conclusion. 



I.— INTRODUCTION. 



Until the last few years most geologists have taught that the glacial 

 period was one of a great submergence of northern land, over which 

 floated icebergs bearing from more arctic regions, stones, gravel and 

 clay. Agassiz had long ago argued that land and not floating ice 

 had been the eSective agent in the glaciation of countries, but his 

 theoiy met Avith little support, until the investigations of ISTorweg- 

 ian and Swedish geologists proved that the glaciation of the Scandi- 

 navian peninsula had radiated from the central mountains, and could 

 not have been produced by currents drifting icebergs from the 

 north. The same result has been worked out in Scotland by Mr. 

 Jamieson, and in North Wales by Prof. Eamsay, and now geologists 

 are agreed that at the time of the greatest developement of the 

 ice in Europe, the land Avas elevated above its present level and 

 covered with ice, which descending from the higher ranges, deepened 

 and widened the valleys doAvn Avhich it floAA-ed. 



The continent of North America is more slaciated than that of 



