The object of this paper is to present an account of the work of the past season upon the moraines and abandoned beaches and outlets of the “thumb” and the Saginaw valley in Michigan.* The “thumb” is that part of the state which projects northward between Saginaw bay on the west and the south end of lake Huron on the east.†
Our previous knowledge concerning the Pleistocene formations of these areas may be epitomized as follows :
Professor T. C. Chamberlin’s map in his report on the “Terminal Moraine of the Second Glacial Epoch”‡ shows the great Saginaw-Erie interlobate moraine of northeastern Indiana and southeastern Michigan projected hypothetically northward well toward the end of the thumb. Another great interlobate, which may be called the Saginaw-Michigan, is also shown on the extreme west of the Saginaw valley, but no other moraines are recorded within these areas. His latest map, issued . . .