140 RELICS OF PRIMEVAL LIFE 



with things of very different character, from which 

 we had taken pains to distinguish them. 



"The united thickness," says Sir WilHam Logan, 

 " of these three great series, the Lower and Upper 

 Laurentian and Huronian, may possibly far surpass 

 .nat of all succeeding rocks, from the base of the 

 Palaeozoic to the present time. We are thus carried 

 back to a period so far remote that the appearance 

 of the so-called Primordial fauna may be considered 

 a comparatively modern event." So great a revolu- 

 tion of thought, and this based on one fossil, of a 

 character little recognisable by geologists generally, 

 might well tax the faith of a class of men usually 

 regarded as somewhat faithless and sceptical. Yet 

 this new extension of life has been very generally 

 received, and has found its way into text-books and 

 popular treatises. Its opponents have been under 

 the necessity of inventing the most strange and 

 incredible pseudomorphoses of mineral substances 

 to account for the facts. As might have been ex- 

 pected, after the publication of the original paper, 

 other facts developed themselves. Mr. Vennor 

 found other and scarcely altered specimens closely 

 allied to the Laurentian forms in the Hastings series 

 of Tudor, probably of Huronian age. Giimbel re- 



