114 HONEYMAN GEOLOGY OF ANTIGONISH COUJNTY. 



fineness and colour to the preceding Devonian. Still, however, the 

 difference between them is obvious, as the carboniferous is arenace- 

 ous, and the difference of inclination manifests unconformability. At 

 Arisaig near McAra's brook, the carboniferous strata are much 

 coarser than at upper South river, but of the same brownish red 

 colour. Here we find the carboniferous sandstones forming moun- 

 tains equal in elevation to the Silurian, having been upheaved by 

 the trap which appears between the supposed Devonian up Mc- 

 Ara's brook and the sandstone of the mountain. But the conglom- 

 erate is by far the most extensively distributed. We find it on the 

 north-east side of Arisaig, and largely developed at Cape St. George. 

 It is found at the south-east side of South river lake, occupying the 

 same position in relation to Devonian here, as the fine brownish red. 

 sandstones to the Devonian at upper South river. It occurs on 

 the south side of the Sugar Loaf north of the town, filling up the 

 great break between this range and the Antigonish mountains. 

 Here its width, or north and south extension, is about five miles. 

 About six miles from the town it attains to a mountain elevation. It 

 runs along the foot of the Antigonish mountains, and terminates 

 apparently where it outcrops near the entrance to the Marshy Hope. 

 I have already noticed this outcrop as succeeding the Devonian, 

 This conglomerate unmistakably declares its age and origin. It was 

 accumulated on the shores of the post Devonian sea, and formed 

 from the felspathic rocks and slates of the mountains. Oxide of 

 iron is its colouring matter, and streaks of green show the existence 

 of thinly distributed carbonate of copper, while carbonate of lime 

 largely agglutinates. The malachite is seen chiefly in the Sugar 

 Loaf and Antigonish mountain conglomerate. Succeeding the upper 

 South river lower carboniferous sandstones we have a thick bed 

 of limestone, which probably owes its existence to organic agency, 

 although it has not yet been found to contain organisms. On the 

 road to Lochaber I found what appears to be a continuation of the 

 same limestone, containing a deposit of beautiful brown ochre, and 

 on the banks of the Ohio river the limestone continues ; this is ex- 

 posed in the bed and on the lofty banks of a small brook which runs 

 into the river. Here the limestone is black and shaly, and contains 

 numerous fossils, among which arc spir'ifcrl sjk '? 2>>'o<l'ic/a sjihiosa, 

 and the pygidium of a Plt'dliysia. This is now the second locality 



