Counts of 626 cobbles from Wisconsin till collected at random showed that not over 3 to 4 per cent of the cobbles show prominent glacial striation or shaping, these characteristics being about ten times as abundant among the limestone cobbles as among the other sedimentary, metamorphic, and igneous rocks. Detailed measurements and evaluation of shapes and markings were made on 300 selected glacial cobbles. These showed a dominance of tabular forms with a tendency toward pointed pentagonal profiles and practically all these were smoothed and rounded on the edges. The dominant striation pattern is a subparallel one which is almost universally parallel to the long axis of the cobble.

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