1921] DACHNOWSKI—PEAT DEPOSITS 65 
within the area of the several great morainic systems, such as the 
Shelbyville, the Bloomington, the Valparaiso-Kalamazoo-Missis- 
sinawa, the Lake Border—Defiance, and the Port Huron, it should 
od 88° 86° 4° 82° oo” i. ee 
~ 
E Up > 
af S fa 
Lb 
Fic. 1.—Diagrammatic outliné of Wisconsin ice ponte we several successive 
positions latter LEVERETT and TAYLor 1g with slight : lines of direction 
of ice movement grees from original map, and names of a few localities with peat 
deposits added by write 
be possible to sum up the whole series of climatic changes which 
have taken place while the ice field receded, and to estimate the 
length of time for every single glacial substage. Primarily because 
