A Three-fold Development. 141 



the great continents and oceans were laid out and de- 

 fined at the beginning, and that the changes in level have 

 been local rather than general; that the great oceans 

 have always been about as they now are, while the con- 

 tinents have held practically the same shape as they now 

 have. A map of the world shows the land surface of the 

 continents radiating away from the north pole, while 

 they all terminate in narrow points before reaching the 

 south pole. As we believe that the land and water sur- 

 face of the globe has been much as it now is from the 

 first, then the north polar regions were the first to be 

 cool enough to support life, and so life probably began 

 in that part of the earth. Paleontologists have found 

 rich fossil bearing rocks of Silurian age beyond 60 de- 

 grees north, and the climate was warm enough as late 

 as the Tertiary age to support a rich tropical life. The 

 south polar regions have been covered by water ever 

 since man has left any record, although when the glacial 

 epoch covered all the northern part of the continents 

 with ice, there may have been and probably was a great 

 extension of the land areas in southern latitudes. It is 

 probable, however, that the continents were shaped out 

 much as they now are from the earliest times, and that 

 life began and spread from the greater land surfaces of 

 the north. It is also believed that formerly the land sur- 

 face extended from the northern part of the American 

 continent eastward by way of Greenland and Iceland, 

 and either connected it with northwestern Europe, or at 

 least much more nearly so than now. 



While we find positive fossils only back to the Cam- 

 brian rocks, we believe and know that the beginning of 

 life was longer in time before that period than has passed 

 since then. The Laurentian rocks are the oldest that 

 have ever been examined by geologists. These, while 

 highly metamorphosed, contorted and folded, are un- 

 doubtedly sedimentary in their origin and were laid down 

 under the ocean. Only a few years ago they were called 

 Azoic, or without life. But one fossil has been described 

 from these rocks, and that is not accepted as a true fossil 

 by all geologists. Prof. J. W. Dawson, of Canada, has 

 described w^hat he believes to be a Foraminifer, one of 



