THE TERRACE EPOCH. 353 



The rolled, sea-worn bowlders, shingle and sand, com- 

 posing the mass of the ancient osars and beach deposits, 

 now found at all heights from the sea-level to those of 

 five hundred or six hundred feet, are derived from the 

 resorting of the moraines. We thus find that the high- 

 est beaches are the oldest, and the most recent, those 

 just above the ocean level. The temperature of the sea 

 did not differ greatly from that of the present day. Dur- 

 ing the epoch the present distribution of the faunae now 

 inhabiting the temperate and arctic zones was estab- 

 lished, and since then but little change has taken place. 

 The fresh-water shells found about the Niagara River 

 and other .deposits in Canada, were, so far as we know, 

 introduced at this time. Those shells found in beach 

 deposits on the St. Lawrence River, from four hundred 

 to five hundred feet above the present level of the river, 

 show that but little change has taken place in the climatic 

 relations of the land or in the distribution of the animals 

 depending on such relations. It is evident that the 

 Acadian fauna, once restricted to the regions south of 

 the Saco River, during this epoch crept up the coast of 

 Maine, extended itself along the western shores of the 

 Gulf of St. Lawrence, and prevailed in the St. Lawrence 

 River, and the broad estuary now represented by Lake 

 Champlain. 



The close of this period witnessed the surface of New 

 England covered by broad lakes and ponds, with vast 

 rivers and extensive estuaries, with deep fiords cutting 

 up the coast-line. Its scenic features must have resem- 

 bled those of Labrador at the present day. 



IV. The Terrace Epoch. The estuaries and deep 

 bays left beach deposits of sand and shingle, resulting 



