34 PROCEEDINGS OF THE NATIONAL MUSEUM vol.76 



are far from complete. The generic types are, however, sufficiently 

 well known to indicate the connection of the Traverse forms with 

 a northern origin. This is to be expected, for there is not the 

 slightest possibility of their origin in the south or west and an east- 

 ern derivation is denied by stratigraphic conditions. It has further 

 been pointed out that the Traverse strata thin to the southward and 

 overlap to the eastward. Thus we come to the conclusion that the 

 Traverse seas successively advanced from the northward across the 

 Laurentian mass into an irregularly and intermittently sinking basin 

 occupying southwestern Ontario, northwestern Ohio, all of the 

 Southern Peninsula, and the eastern part of the Northern Peninsula 

 of Michigan, and opening by way of James Bay and Hudson Bay 

 to the Arctic and the North Atlantic Oceans. 



D. S. GOVHBNMHNT FBINTINO OFFICE: 1»2» 



