56 THE EOZOON. PART in. 



portions appear to have been fossilized before the newer 

 were built up on them as a base, exactly like the coral 

 reefs in the tropical ocean of the present day, 1 with 

 this difference however, that shells and other crusta- 

 ceans are associated with the corals, while no organic 

 I body has been found in the Eozoon reefs ; nevertheless 

 the Eozoon must have had food. It may therefore be 

 inferred that parts at least of that primeval ocean 

 swarmed with animal life, whose remains have been 

 obliterated by metamorphic action. Carbon (which in 

 the form of graphite both constitutes distinct beds, and 

 is disseminated through the siliceous and calcareous 

 strata of the Laurentian series, as well in Norway as in 

 Canada), may indicate the existence of vegetation in the 

 Eozoon period. 



/ The Eozoon is by no means confined to Canada and 

 I central Europe. The serpentine marble of Tyree which 

 forms part of the Laurentian system on the west of 

 Scotland, and a similar rock in Skye, when subjected to 

 minute examination, are found to present a structure 

 clearly identical with that of the Canadian Eozoon. 

 And the like structure has been discovered by Mr. 

 Sanford in the serpentine marble of Connemara, known 

 as Irish green. The age of that rock however, is 

 doubtful : for when it was discovered to contain Eozoon, 

 Sir Eoderick Murchison who had previously studied its 

 relations was at first inclined to believe it belonged to 

 the Laurentian series ; now however, he considers the 

 Connemara marble to be of the Silurian age. ' If this be 

 the case it proves that the Eozoon was not confined to 

 the Laurentian period, but that it had a vast range in 

 time, as well as in geographical distribution ; in this 

 respect corresponding to many later forms of Foramini- 

 fera which ha,ve been shown by Messrs. Parker and 



1 Structure of the Organic Remains in the Laurentian Rocks of Canada : 

 by J. W. Dawson. Esq., Principal of M'Grill University, Montreal. 



