NOVA BCOTIA. 56] 



extending through Mount Thorn, imperfectly connect* it with tlio 

 tern extremity of the ( !obeqnid range; of hills. In the hill) country 

 connected with Mount Thorn, and in the \ricinitj of the apper parti 

 of the Salmon, West, and Middle Rivera, conaidenble breadths of 

 Lower Carboniferous strata have been partially metamorphosed, and 

 invaded by greenstone anil other igneous rocks. It is also quite pos- 

 sible that portions of the rocks here cropping out from beneath the 

 Carboniferous may he Devonian. A mass of granite, containing dark 

 gray felspar, abundance of black mica, and very little quarts, ocean 

 on the cast side of Mount Thorn. This is the only instance, bo far as 

 I am aware, of the occurrence of true granite in this group of rocks 

 in this part of Nova Scotia. 



The Cobequid //ills, extending nearly in an east and \\< ssl direction 

 for about ninety miles, in that part of Nova Scotia lying north of the 

 southern arm of the Bay of Fundy, must be referred to the mctamor- 

 phic group now under consideration. Both their stratified and igneous 

 rocks arc similar to those of the parts of this group already described. 

 Fossils are absent or very rare in those parts of them which I have i \- 

 plored, with the exception of Earlton, in the eastern extremity of the 

 range, where there are slates containing fossils similar to those already 

 noticed. I shall make no attempt to descrihe the numerous and 

 singular varieties of altered and igneous rocks found in the Cobequid 

 range, hut shall content myself with a description of its structure 

 in its central portion, which is illustrated by the general section 

 attached to the map. 



On the northern side of the hills, near the post road from Truro to 

 Amherst, and also on Wallace River, the lowest rocks of the Carbon- 

 iferous system, consisting of reddish-brown conglomerates, arc seen 

 at the base of the hills. Their dip is to the northward at a high angle. 

 On ascending the hills, masses of red, flesh-coloured, and gray syenite 

 are seen, and rise rapidly to the height of several hundred feet ; the 

 northern side of the range being steeper and more lofty than the 

 southern. The syenite of this part of the hills has often been described 

 as a granite; but wherever I have observed it, it is a true syenite, 

 containing reddish or white felspar, black hornblende, and marly 

 colourless quartz. Some of the red varieties are large grained and 

 very beautiful. The gray varieties are often tine grained, and appear 

 to pass into greenstone. 



It is remarkable that the syenite and greenstone of this part of the 

 mountain are traversed by numerous small veins of true granite. 

 Whether these have been produced by segregation, or arc parts of a 

 later outburst of granitic rock, I cannot determine with certainty, but 



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