Carloniferous System in Eadeni Canada. 161 



Carboniferous — is the question occupying our minds dur- 

 ing the present collecting season. 



It appears from evidence at hand that these limestones 

 do not constitute the base of the Carboniferous system in 

 the Maritime Provinces, although they contain the earliest 

 types of Marine Carboniferous seen in Eastern Canada. 

 The occurrence of this formation in certain definite 

 areas of Nova Scotia marks a cessation of the conditions 

 existing in the areas which these limestones cover, 

 indicating that the sea or Atlantic waters in Carboniferous 

 times extended over the Eo-Carboniferous deposits pre- 

 viously laid down, which had been subjected to elevation 

 and erosion previous to their being overlaid, whilst the 

 vegetation and climate of this period did not probably 

 change very materially during this period of submergence 

 and encroachment of the sea. A period of elevation then 

 followed in which sandstones and shales were deposited, 

 to be followed later again by sandstones, the shales and 

 coal seams peculiar to the Coal Measures and Millstone 

 grit underlying them. 



The terrigenous origin and nature of the Coal Measures 

 need not be described. The flora and fauna they hold 

 mark estuarine conditions existing and prevailing with a 

 luxuriant growth of plants on land with various kinds of 

 animals in the water and on land also. 



A brief summary of the succession of the sediments in 

 the Carboniferous of Nova Scotia in Pictou and Col- 

 chester and Cumberland Counties in part would give the 

 following succession arrano;ed in ascending order : — 



I. RiVERSDALE AND Union FORMATIONS, with volcaiiic rocks and 



associated strata constituting one series, consisting of red 

 sandstones, shales and conglomerates with carbonaceous 

 shales and sandstones, with occasional bands of calcareous 

 matter, besides diorite and other basic rocks, which together 

 measure upwards of 10,000 feet in thickness, the equivalent 

 of the Calciferous Sandstones of Great Britain. 



II. An unconformity. 



