Tin: LAUUENTIAN. 



89 



stones I have recognised somewhat obscure structures, which appear 

 to indicate the presence of fragments of Eozoon.* In consequence of 

 this discovery, I reprint here some illustrations of the structure of the 

 typical Canadian Eozoon, as guides to observers searching for them 

 in the Laurentian of the Lower Provinces (Figs. IG and 17). Full 

 descriptions and other details will be found in my work, " Life's 

 Dawn on Earth." f 



Fig. IG.—Eoxooii Canadense. 





(1) Weathered specimen, natural size. 



(2) Casts of Acervuline chamljers. 



(3) Surface of a flat chamber. 



(4) Section showing casts of flat cliambers. 



Dr Hunt seems, in recent publications, inclined to doubt the Lauren- 

 tian age of the upper part of these rocks, and to refer them, with the 

 Hastings group of Ontario, to a somewhat later though pre- Cambrian 



age. 



Dr Iloneyman and Professor Hind have suggested the Laurentian 

 age of certain rocks at Arisalg, in the Cobequids, and associated with 

 the coast Metamorphic scries, but I do not regard the evidence of this, 

 cither from fossils, mineral character, or superposition, as conclusive, 

 andmust refer for it to the memoirs of these gentlemen in the Trans- 

 * I'roceedings, American Associatujn, 187G. f T.oudoii, 1S75. 



