Image Description from historic lecture booklet: "If a region is marked by deep valleys and high hills, and a great glacier comes over it, the overriding and grinding of the ice will subdue the hill tops and hillsides, scour away frail ridges and sharp summits, and leave it a region of oval crests. Such hills are shaped like drumlins, but are often much higher and steeper, and, unlike the drumlins, consist of bed-rock, except the surface coating of boulder clay. They often show a somewhat fluted surface, the fluting being parallel with the longer axis of the elevation."