J. E. Todd — Revision of the Moraines of Minnesota. 475 



The Fourth moraine, namely that crossing Lake Traverse 

 and lying along the east side of Big Stone Lake and Minnesota 

 River and connecting with the main moraine upon the east in 

 Pope County, or Mr. Upham's 7th moraine, is quite feebly 

 developed, which corresponds to the reduced strength of the 

 western ice lobe. This rapid recession from the west and 

 south seems a natural consequence of its greater exposure to 

 the warm southwestern winds. 



We are unable to follow Mr. Upham in his recognition of 

 the Kiester, Elysian and Waconia moraines, for they seem to 

 us based upon reentrant angles of the Third moraine. It is 

 probable that during the formation of the Fourth moraine the 

 separation of the ice lobes had extended as far north as the 

 Leaf Hills in the southern part of Otter Tail County. It is 

 impossible, from our present knowledge of the region, to satis- 

 factorily analyze the very complicated tangle of morainic 

 ridges which are included under the general head of Leaf Hills. 



In eastern Clay County a spur of the western branch of the 

 interlobular moraine indicates a Fifth moraine, which seems to 

 have been overlooked by Mr. Upham. The junction of this 

 moraine with the highest beach of Lake Agassiz is shown 

 upon the map of Clay County in the second volume of the 

 Geological Survey of Minnesota. At that time, if we inter- 

 pret rightly, the reentrant angle of the moraine extended 

 probably as far north as the head waters of the Wild Rice ; 

 and considerable drainage from the western lobe escaped down 

 the valley past Detroit by the upper course of Pelican River. 

 Probably at the same time, although not certainly, the edge of 

 the Lake Superior lobe was forming the moraine which passes 

 through range 39 along the east side of Otter Tail River and 

 Otter Tail Lake past Osakis Lake and along Sauk River. It 

 seems not improbable that the morainic portion in eastern 

 Sherburn County belongs to this stage, and even as late as this 

 the ice may not have withdrawn to any extent from the St. 

 Croix River on the east. 



South of the Wild Rice another prominent moraine disap- 

 pears in the bed of Lake Agassiz, which we will call the Sixth. 

 At that time, if we comprehend rightly, the lobes had been 

 separated along the line curving quite sharply eastward in 

 southern Beltrami County. The two members of the moraine 

 pass on opposite sides of the lower Wild Rice Lake and 

 become united and gradually disappear at a point on the divide 

 north of Lake Bern id ji. To this stage we would refer, with 

 considerable confidence, the morainic accumulations about. Lake 

 Itasca, which, as we have before suggested, we consider a reen- 

 trant angle pointing eastward, ow T ing its existence to the ele- 

 vated character of that region. The region about Itasca in 



