140 THE ICE AGE IN CANADA. 



extensively deposited in the Acadian bay, and in part have 

 been raised out of the water in Prince Edward Island, 

 while the whole bay was shallowed and in part cut off 

 from the remainder of the gulf by the elevation of ridges 

 of lower Carboniferous rocks across its mouth. In the 

 Post-pliocene period, that which immediately precedes our 

 own modern age, as I have elsewhere shown,* there was 

 great subsidence of this region, accompanied by a cold 

 climate, and boulders of Laurentian rocks were drifted 

 from Labrador and deposited on Prince Edward Island 

 and Nova Scotia, while the southern currents, flowing up 

 what is now the bay of Fundy, drifted stones from the 

 hills of New Brunswick to Prince Edward Island. At 

 this time the Acadian bay enjoyed no exemption from the 

 general cold, for at Campbelltown, in Prince Edward 

 Island, and at Bathurst, in New Brunswick, we find in the 

 clays and gravels the northern shells generally character- 

 istic of the Post-pliocene ; though perhaps the lists given 

 by Mr. Matthew for St. John and by Mr. Paisley for the 

 vicinity of Bathurst, may be held to show some slight 

 mitigation of the arctic conditions as compared with the 

 typical deposits in the St. Lawrence valley. Since that 

 time the land has gradually been raised out of the waters, 

 and with this elevation the southern or Acadian fauna 

 has crept northward and established itself around Prince 

 Edward Island, as the Acadian bay attained its present 

 form and conditions. But how is it that this fauna is now 

 isolated, and that intervening colder waters separate it 

 from that of southern New England ? Verrill regards this 

 colony of the Acadian bay as indicating a warmer climate 

 intervening between the cold Post-pliocene period and the 



* Notes on Post-pliocene of Canada, Canadian Naturalist, 1872. 



