THE LAUUENTIAN SYSTEM. CG3 



thick beds at M'Closkeney's and Drury's Coves on the Kenncbcckasis, 

 and again, on the St John side of an anticlinal funned by the syenitic 

 or gneissose rocks, at the suburb of Portland. These limestones are also 

 well seen in a railway-cutting five miles to the eastward of St John. 

 and at Lily Lake. Near the Kenncbcckasis they an unconfonnably 

 overlain by the Lower Carboniferous conglomerate, which is eoar •• 

 and of a red colour, and contains numerous fragments of the limestone. 



" At Portland the crystalline limestone appears in a very thick bed, 

 and constitutes the ridge known as Fort Howe Hill. Its colours 

 are white and gray, with dark graphitic lamina; and it contains 

 occasional bands of olive-coloured shale. It dips at a very high angle 

 to the south-cast. Three beds of impure graphite appear in its upper 

 portion. The highest is about a foot in thickness, and rests on a sort 

 of underclay. The middle bed is thinner and less perfectly exposed. 

 The lower bed, in which a shaft has been sunk, seems to be three or 

 four feet in thickness. It is very earthy and pyritous. The great 

 bed of limestone is seen to rest on flinty slate and syenitic gneiss, 

 beneath which, however, there appears a minor bed of limestone." 



Their structure is more fully represented in the following section 

 by Mr Matthew. The order is ascending : — 



" 1. Gray limestones and dolomites (?) of great thickness, with beds 

 of clay slate, occupying the middle of the peninsula which separates 

 Kennebeckasis Bay from the Bay of Fundy. 



" 2. A mass of syenite and protogene, probably metamorphosed 

 sediment. 



" 3. Gray and white limestones and beds of syenitic gneiss. 



" 4. Gray and reddish gneiss, conglomerate, and arenaceous shale, 

 altered, resembling syenite and granulite. Arenaceous shale and 

 gray quartzitc. Dark flinty slate, with oval grains (black). 



" 5. Graphitic shale and pyritous slate, frequently alternating with 

 gray and white limestones and dolomites (?). The beds thinner, 

 and alternations more frequent, towards the top." 



I have searched in vain, in the specimens in my possession, for 

 indications of the characteristic fossil of the Laurentian ; but there 

 are traces of vegetable tissues, probably fucoidal, in the graphite and 

 graphitic shale ; and in rocks at Sand Point, referred by Mr Matthew 

 to this group, there are worm-burrows and other markings, probably 

 of organic origin. No representatives of the great deposits of iron 

 ore found in the Laurentian of Canada and New York, have yet been re- 

 cognised in New Brunswick. Nor do we know of anything correspond- 

 ing to the interesting auriferous veins of Madoc, in Upper Canada 

 (Ontario). The limestone of Portland, however, and other plao -. 



