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which, as far as we at present know, are, with the exception of eozoon, 

 quite destitute of organic remains. This latter is the Laurentian 

 System which we are to consider for a few minutes this evening. In 

 many localities the overlying series of schists is wanting, so that the 

 newer fossiliferous rocks repose directly on this older gneissic system. 

 The Laurentian is then the foundation on which all the more recent 

 systems are laid down. It is the only universal formation, since it 

 exists in all parts 'of the world, although in most places concealed by 

 newer deposits. This great system, of crystalline rocks, although 

 pretty uniform in lithological characters, is known by different names 

 in the diffei^ent countries where it has been studied. The name 

 Laurentian, fi-om the River St. Lawrence, along whose northern shore 

 it extends for several hundred miles, was given to it by Sir William 

 Logan, who spent much time in studying it during the earlier years of 

 the Geological Survey of Canada. In Germany and Scandinavia it 

 forms the lower portion of the " Grundgebii'ge." It has also been called 

 " Urgebirge," the Piiraitive Formation, and forms part of the Archean 

 System of Dana. 



In addition to the large areas over which the Laurentian is exposed 

 in North America, it is extensively developed in various other parts of 

 the world. In Europe it is most widely s])read in Scandinavia and 

 Finland, but occurs in Bavaria, Bohemia, and probably Silesia, in 

 Germany, as well as in the north of Scotland, and probably in many 

 other localities. Baron von Richthofen has recently described the 

 occurence of two unconformable series of gneisses in China, both of 

 which he correlates with the Laurentian System. He states, however, 

 that they are destitute of crystalline limestone. In India immense 

 areas of gneissic rocks have been mapped by the Geological Survey of 

 that country. Similar rocks are also found in Japan and in south-east 

 Africa, and occur over very extensive areas in Brazil, Venezuela, Chili, 

 and the Guianas. 



The area occupied by Laurentian rocks in Canada was estimated 

 by Sir William Logan to be about 200,000 squai-e miles. Speaking 

 generally we may say that they form a band extending from 

 Labi'ador to the Ottawa, and which, after sending a spur across the 

 boundary line into the United States, forming the Adirondacks, takes 



