108 THE DAWN OF LIFE 



ore beds of the Silurian rocks. May not similar causes have 

 been at work in the Laurentian period ? 



Any one of these reasons might, in itself, be held insufficient 

 to prove so great and, at first sight, unlikely a conclusion as 

 that of the existence of abundant animal and vegetable life in 

 the Laurentian ; but the concurrence of the whole in a series 

 of deposits unquestionably marine, forms a chain of evidence 

 so powerful that it might command belief even if no fragment 

 of any organic and living form or structure had ever been 

 recognised in these ancient rocks. 



Such was the condition of the matter until the existence of 

 supposed organic remains was announced by Sir W. Logan, at 

 the American Association for the Advancement of Science, in 

 Springfield, in 1859 ; and we may now proceed to narrate the 

 manner of this discovery, and how it has been followed up. 



Before doing so, however, let us visit Eozoon in one of its 

 haunts among the Laurentian Hills. One of the most noted 

 repositories of its remains is the great Grenville band of lime- 

 stone ; and one of the most fruitful localities is at a place 

 called Cote St. Pierre on this band. Leaving the train at 

 Papineauville, we find ourselves on the Laurentian rocks, and 

 pass over one of the great bands of gneiss for about twelve 

 miles, to the village of St. Andre" Avelin. On the road we see 

 on either hand abrupt rocky ridges, partially clad with forest, 

 and sometimes showing on their flanks the stratification of the 

 gneiss in very distinct parallel bands, often contorted, as if the 

 rocks, when soft, had been wrung as a washerwoman wrings 

 clothes. Between the hills are little irregular valleys, from 

 which the wheat and oats have just been reaped, and the tall 

 Indian corn and yellow pumpkins are still standing in the 

 fields. Where not cultivated, the land is covered with a rich 

 second growth of young maples, birches, and oaks, among 

 which still stand the stumps and tall scathed trunks of enor- 

 mous pines, which constituted the original forest. Half way 



