CARBONIFEROUS OF CAPE BRETON—GILPIN. 33 
eastern limits the Pre-Cambrian of the interior and the valley of 
the lower part of the North-East Margaree. These strata are 
non calcareous and in great measure must be considered as 
representing the basal conglomerates which I have referred to 
as characteristic of the Carboniferous of the Sydney district, 
while the more altered sections are possibly to be regarded ‘as 
lower than the commonly accepted dividing line between the 
Carboniferous and Devonian. 
The Marine Limestone formation in this part of Cape 
Breton presents the same typical features which lead to its easy 
recognition in all parts of the Maritime Provinces. In the 
extreme part of Cape Breton it extends from Cape St. Lawrence 
to Cape North, and nearly joins the exposure of the same horizon 
at Aspy Bay, which, following the valleys of the Brooks, runs 
far into the island. At Ingonish, and along the shore from Cape 
Enfume to St. Anne’s Harbour, there is a narrow strip of the 
marine limestone, which follows the valleys of the St. Anne 
rivers for several miles until it is sueceeded by the Pre-Cambrian 
felsites. Through St. Anne’s this horizon is continuous to Bad- 
deck and connects with the larger exposures of Carboniferous in 
Inverness County. From Baddeck it follows the valley of the 
Middle River in a narrow tongue, and connects with the same 
measures filling the valley of the Margaree and its principal 
branches. In the opposite direction it one from Baddeck 
through the River Denny’s Basin into the watershed of the 
River Inhabitants, and passing between the Malagawatch and 
Craignish Hills ends on the Strait of Canso at Plaster Cove, and 
on the Bras d’Or at the head of West Bay. 
Another band lying west of the Craignish Hills, and the 
belt of altered Lower Carboniferous already referred to, runs from 
Judique to Mabou and passing to the east of the felsitie high- 
lands of Cape Mabou extends to Lake Ainslie. Here it surrounds 
some outliers of the “ altered ” rocks referred to above, and con- 
tinues in the rear of the Broad Cove and Chimney Corner coal 
district, until it meets the valley of the North West Margaree. 
Another narrow strip skirts the eastern shore of Lake Ainslie. 
There are many small isolated patches of these measures along 
