POSTGLACIAL BIOTA OF THE GREAT LAKES REGION 167 



In North Dakota, near Repon, Cass County, Elephas remains have been 

 found in the Herman beach of Lake Agassiz, about one foot below the surface 

 of the Wisconsin till sheet, and below the gravel of the beach. 171 



The mastodon was rare in Minnesota, judging by the absence of authentic 

 records. A tusk eight and a half feet in length is reported from Northfield, 

 Fairebault County, in drift ten feet below the surface. 172 A jaw bone is also 

 reported from a gravel bank at Albert Lea, Freeborn County. 173 Proboscidian 

 remains, either mastodon or elephant, have been reported from various places 

 in Minnesota as noted below: 174 



Minnesota City, Winona Co., and Stillwater Washington Co., in terrace 

 gravel of flood plain stage of Wisconsin time. Minneapolis, Hennepin County. 

 Minnetonka, Hennepin County. Mankato, Blue Earth County. 



Bison latifrons is recorded by Winchell 175 from Mora, Kanabec County, in 

 clay of ditch, several feet below the surface. Ovibos cavifrons 176 is also reported 

 by Winchell from between Wabasha and Thielman, in the gravel terrace of 

 the valley, ten feet below the surface. Winchell places the deposit as probably 

 in the Wisconsin terrace epoch or possibly in Iowan loess. As the deposit 

 may be of Peorian age, it is also recorded in Chapter X, page 351. 



"In the vicinity of the Lake of the Woods, horizontally bedded, finely 

 laminated, yellowish-gray, silty clay occurs, which in places occupies the sur- 

 face up to a height of 15 or 20 feet above the lake and unconformably overlies 

 the yellow till or bluish laminated stony clay. Fresh water shells are numer- 

 ous in the deposit. 



"The presence of the shells in these deposits and in many of the beach 

 ridges in this district up to an altitude of at least 140 feet above the lake sug- 

 gests a correlation in time and that different conditions existed at the time of 

 the deposition of the lacustrine clays than when the glacio-lacustrine deposits 

 were laid down. " 176a 



TV. Records of Life Outside the Area and Influence of the Great 



Glacial Lakes 



The remains of postglacial biota have been found in places remote from the 

 large lakes formed by the retreating ice. These remains are usually found in 

 marl beds of small lakes, in river terraces and in ancient soil formations. Only 

 a few records of such are available. These are listed by states. 



171 Upham, Glacial Lake Agassiz, p. 322. 



172 Geol. Nat. Hist. Surv. Min., Final Rep., I, p. 670. 



173 Op. cit., p. 386. 



171 Bull. Min. Acad. Sci., IV, pp. 414-422. 



175 Bull. Min. Acad. Sci., IV, No. 3, pp. 414-422. 



178 Op. cit., page 420. 



17ea Johnston, Summary Report, Can. Geol. Surv., 1913, pp. 173, 174. 



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