This study was begun with the idea that the conclusion would he the certain transferal of the Morrison to the Lower Cretaceous or Comanchian. The writer, from a preliminary study made two years ago of some of the results of the findings in Bast Africa, was led to this belief, but as the final study progressed it became plain that if the Morrison could be shown to lie of Comanchian time at all it would have to he referred to the earliest part of this period. To make certain of the facts, the writer took up correspondence with several of his friends, resulting in the conclusion that for the present the Morrison is best left in the Jurassic, where it has been placed by most American paleontologists.

The marine Sundance beneath the Morrison has several forms of ammonites, one of which is Cardioceras cordiforme, a species of great stratigraphic significance. . . .

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