470 Canadian Record of Scienec. 



Review of the Evidence for the Animal Nature of 

 Eozoon Canadense. 



By Sir William Dawson, C.M.G., LL.D., F.R.S., Etc.* 

 I. HISTORICAL AND STRATIGRAPHICAL. 



The writer of these notes had hoped to have been able 

 long ago to let the vexed questions respecting Eozoon 

 repose in peace in so far as he was concerned, and he is 

 now induced to offer a short summary of the evidence in 

 the case only with the view of correcting some misappre- 

 hensions that seem to have arisen in regard to points well 

 ■established, and which, independently of any question as 

 to the nature of Eozoon, belong to the certain data of 

 geology. These misapprehensions lead to the confound- 

 ing of the structures originally discovered by Logan with 

 things in no way related to them, and from which they 

 had been clearly distinguished by my own original studies, 

 and by those of Hunt, Carpenter, and Rupert Jones. New 

 facts relating to pre-Cambrian life have also been coming 

 to light from time to time, and many of these are con- 

 nected, either directly or indirectly, with the evidence 

 respecting Eozoon. 



As early as 1858, Sir William Logan had begun to 

 suspect that the Stromatoporoid forms collected from the 

 great Laurentian limestones in different parts of Canada 

 must be of organic origin, and he ventured to mention 

 them as possibly of this nature at the meeting of the 

 American Association in 1859, and in his General Report 

 on the Geology of Canada in 1863. The evidence on 

 which he relied was their occurrence only in the lime- 

 stones, their similarity in form and general structure to 

 the Stromatoporae, or "Layer-Corals" of the Palaeozoic, and 

 the circumstance that, while the forms and structures 

 seemed to be identical, they were mineralized by Serpent- 



1 [Reprinted from the Geological Magazine, Decade IV., Vol. II., October, Novem- 

 ber, December, 1895.] 



