PRE-CAMBRIAN LIFE 75 



logical Society of London, the name " Eozoon 

 Canadense " being proposed for the species. Its 

 description was accompanied by a paper on the 

 geological conditions by Logan, and one on the 

 chemical conditions by Sterry Hunt, while sup- 

 plementary notes were added by the late Dr. 

 Carpenter and Professor T. Rupert Jones. Thus 

 launched on the scientific world, " Eozoon " at once 

 became a fertile subject of discussion, and volumes 

 of more or less controversial literature have appeared 

 respecting it. It still has its friends and opponents, 

 and this may long continue, as so few scientific men 

 are sufficiently acquainted on the one hand with the 

 possibilities and conditions of the preservation of 

 fossils in crystalline rocks, and on the other hand 

 with the structures of modern " Protozoa." Thus, few 

 are in a position to form an independent judgment, 

 and " Eozoon " has met with some scepticism on the 

 part both of biological and mineralogical specialists. 



To aid us in forming an opinion, it will be 

 necessary to consider the oldest known strata of 

 the earth's crust, and the evidence which they afford 

 of the condition of the world when they were de- 

 posited. As preliminary to this, we may look at the 

 following table of pre-Cambrfan formations in Canada. 



