GLACIAL DRIFT ON THE MAGDALEN ISLANDS. 
11 
altogether unlike that on Prince Edward Island, where, as others 
have reported, the ground moraine is composed almost exclusively 
of weathered material from the underlying red sandstone, and 
striated ledges are very difficult to find. The stony sands which 
cover the decayed rock in several of the localities on the Magdalens 
and which contain not only the diabase from adjacent hills but 
also stones of several types foreign to the islands, require a trans- 
porting agency which must be either floating sea ice, as Dr. 
Chalmers and Dr. Clark have supposed, or glacial ice. The 
presence of soled and striated pebbles on Amherst and Alright 
islands would not seem to fully settle the question of the nature 
of this ice, although for the production of longitudinal striae 
on pebbles it is thought that an ice sheet furnishes the better 
opportunity. The thickness of the mantle of boulder clay on 
Amherst island, together with its physical and lithological 
heterogeneity, furnish the main ground for the belief that con- 
tinental ice has covered the Magdalens. 
