MAN AXI) THE GLACIAL PERIOD. 663 



Kandiyohi county. Probably nearly all of the southern half of 

 Minnesota was at this time divested of its ice-mantle, while 

 nearly all of the northern half was still ice-covered, the glacial 

 boundary across the State passing in an approximately east to 

 west course not far from Little Falls. 



By its next recessions the ice-border was withdrawn to the 

 eighth or Fergus Falls moraine, and the ninth or Leaf Hills 

 moraine. These are merged together in the prominent accu- 

 mulations of the Leaf Hills, which reach in a semicircle from 

 Fergus Falls to the southeast, east, and northeast, a distance 

 of fifty miles, marking the southern limits of this ice-lobe when 

 it terminated nearly due west of Little Falls and half-way be- 

 tween the south and north borders of Minnesota. Conspicuous 

 morainic hills a few miles east of Little Falls, and others in 

 the north part of Morrison county and along its west side, 

 seem to be correlated with the Fergus Falls moraine. Much 

 of the modified drift of the Mississippi Valley at Little Falls 

 was probably deposited when the ice-sheet terminated at these 

 hills five to fifteen miles distant on the east, north, and west. 

 Eastward from Morrison county, this moraine continues north- 

 east to the north side of Mille Lacs, thence probably through 

 the south edge of Aitkin county and the north part of Pine 

 county, and onward northeasterly to the west end of Lake 

 Superior. The Leaf Hills moraine extends from the northeast 

 part of the Leaf Hills, near the Leaf Lakes, east across northern 

 Todd county and northwestern Morrison county and then 

 north-northeast by Gull, Pelican. White Fish, and Crooked 

 Lakes. Xext it probably takes an eastward course, crossing 

 the Mississippi several miles north of Sandy Lake and the 

 St. Louis River near the mouth of the Cloquet, and thence 

 an east-northeast course passing not far south of the Cloquet 

 River and reaching the north shore of Lake Superior about 

 half-way between Duluth and Pigeon Point. The upper portion 

 of the modified drift at Little Falls, probably including the 

 stratum of chipped fragments of quartz, is referable to the 

 time of the recession of the ice-sheet north from the Fergus 

 Falls moraine to the Leaf Hills moraine. At the west end of 

 the Leaf Hills and thence through a distance of fifty miles 

 northward, this stage of recession carried the ice-border 



