A pre-Cam- 

 brian system 

 eliminated 

 from the 

 Cambrian of 

 Cape Breton. 



12 



island in St. Andrew's channel and at McLean point to the south-west 

 of Long island (the west point of Barachois harbour) convinced him that 

 this resemblance was not accidental, and that the series bore the 

 same relation to the Cambrian that the resembling beds in St. John 

 county, New Brunswick did. This conclusion was confirmed by ob- 

 servations on Indian brook, where similar rocks were found to bear 

 the same relation to the effusives which underlie the Etcheminian. 



Tiiis series as seen on Long island consists of dark gray limestone 

 with layers of calciferous schist, frequently alternating, and dolomitic 

 limestone, having beds of dark gray to black silicious schist, also dark 

 gray feldpathic schist. At McLean point the same limestones are 

 seen in a much less altered condition, and on the road further south-west 

 black flinty shales occur. Similar rocks occur at McSween brook. 

 Other exposures of this series are met with at McLean brook, Shen- 

 acadie, where the section ccurs described by Mr. Fletcher in the 

 Report of Progress, 1876-77, page 431. 



Beside their resemblance to the ' Upper Series ' of the Laurentian 

 in St. John county, this group is thought not to be Cambrian for the 

 following reasons : 



1. No similar series has been met with by me in the Cambrian rocks 



of Cape Breton or elsewhere. 



2. They are cut by granitic veins ; the Cambrian is not. 



3. Similar rocks in the Indian Brook district have furnished pebbles 



to the Cambrian conglomerates. 



4. These rocks are cut by red granite which has also furnished pebbles 



to the Cambrian conglomerates. 



I conclude therefore that this group should be detached from the 

 Cambrian, and should probably go with the George river limestones. 



THE CAMBRIAN SYSTEM. 



THE COLDBROOK TEBRANE. 



The Cold- The relation of this terrane to the Laurentian Upper Series below 



brook terrane. an( j Q tne overlying sedimentary Cambrian, are well shown at Long 

 island in St. Andrews' channel. 



Here along the north-western shore of the island the contact 

 between these effusive rocks and the metamorphic ' Upper Series ' is 

 visible. The lower layers of the Colclbrook are gray ash rocks, more 



