270 THE CARBONIFEROUS SYSTEM. 



the formation seen below White's Plaster Rock, and it is worthy of 

 note, that it is here much moi'e fossiliferous than in the lower part of 

 the river. Lastly^ From the point of the Gore Mountain, along the 

 base of the Douglas and Rawdon Hills, we can trace the Lower Carbon- 

 iferous shales all the way to Horton. That trough-shaped arrangement, 

 so characteristic of the Carboniferous rocks in this part of Nova Scotia, 

 can therefore be traced even in the fractured section of the Shu- 

 benacadie. 



Eastward of the Shubenacadie, the Carboniferous district splits into 

 three branches, entering between the hilly ridges of the metamorphic 

 country to the eastward. The most northern of these passes along the 

 valley of the Salmon River, and is connected with the Pictou district. 

 The second passes up the valley of the Stewiacke River. The third 

 forms a narrow band extending from the Grand Lake nearly to the 

 sources of the Musquodoboit River. In the northern branch, both the 

 Lower Carboniferous and Coal formation series appear, as we have 

 already noticed ; but in the two others the Lower Carboniferous rocks 

 prevail almost or altogether to the exclusion of the Coal formation. 

 In one place only on the Lower Stewiacke, do rocks having the aspect 

 of Coal measures appear. In the Stewiacke branch, which, in the 

 period in question, must have been a sheltered bay or channel, the 

 corals and shells of the limestones attain a magnitude and perfection 

 not, so far as I know, equalled in any other part of the province. 

 Gypsum also abounds in this branch, and in one place there is a large 

 deposit of sulphate of barytes. In the southern or Musquodoboit 

 branch there is much gypsum and also limestone ; but the latter does 

 not appear to be rich in fossils. I have found in it only a few 

 fragments of Crinoids. 



As the district just described presents the most important develop- 

 ment in the province of the Lower Carboniferous series, I have 

 employed it to introduce the reader to that part of this great system 

 of rocks, just as the Cumberland district served a similar purpose in 

 relation to the Coal measures ; and I may now conclude by a review 

 of the condition of Southern Hants and Colchester at the time when 

 the marine limestones and gypsums were produced. At this period, 

 then, all the space between the Cobequids and the Rawdon Hills was 

 an opeir arm of the sea, communicating with the ocean both on the 

 east and west. Along the margin of this sea there were in some 

 places stony beaches, in others low alluvial flats covered with the 

 vegetation characteristic of the Carboniferous period. In other places 

 there were creeks and lagoons swarming with fish. In the bottom, 

 at a moderate distance from the shore, began wide banks of shells and 



