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DRUMLIN, OSAR AND KAME FORMATION.
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it over a much greater area than it originally occupied, forming a secondary train. The erratics of this secondary train, he finds much smaller in general and marked by greater evidence of glacial reduction than those of the unmodified later train. This has a double bearing upon the question of the origin of the drumlins in that it indicates basal transportation in both epochs and in that it indicates a direct accumulation of the drumlins de novo during the later incursion. It seems to exclude the view that the drumlins are remnants of the older drift; for, since the older train was westerly, there would be no quartzite material in the old drift lying southwesterly from the outcrops, and hence none would appear within the body of the drift in that region when worn into drumlin forms. But it is just here that quartzite erratics appear in their greatest abundance and permeate the body of the drumlins most impartially. The direct south-southwesterly bowlder train is so predominant that the older, and now more scattered, westerly one was not recognized by the earlier observers.

The testimony of these bowlder trains (basal phenomena distributed along the line of drift movement) combined with that of the border belts (superficial phenomena distributed transversely to the drift movement and parallel to the edge of the ice) seems therefore to add some special weight to the already familiar evidence supporting the view that drumlins are strictly basal aggregations.

There are no well defined osars (eskers) in this drumlin region, but there are tracts of gravelly knolls and ridges some of which seem to represent longitudinal glacial drainage lines, and so, genetically speaking, to stand for the esker phenomena. Aggregates of the kame type, or of an unclassifiable type of this general order, occur not infrequently among the drumlins. In connection with the moraines bordering the district, kames of the typical variety have an abundant development. Into all these, so far as they lie within the area of quartzite distribution, the quartzitic material enters in even greater abundance than into the average unmodified till of the drumlins themselves or

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