NAME IN MEMORY OF LOUIS AGASSIZ. 5 



upon all the glaciated area of our continent from New England to British 

 Columbia. The ice-sheet of northwestern Europe also formed such lakes 

 during its final melting. Some of these lakes, pent np in valleys 2,000 to 

 3,000 feet above the sea, between the eastern side of the Scandinavian 

 Mountams and the remnant of the ice still covering eastern Sweden, 

 attained lengths of about 100 miles and depths of about 1,000 feet.-^ In 

 Scotland, likewise, the famous Parallel Roads of Glen Roy are shown to be 

 the shores of successive stages of a lake held by the ban-ier of the waning 

 Scottish ice-sheet.^ The positions of the European glacial lakes, as of 

 those in North America, were determined by the areas of g-reatest thickness 

 of the ice and the manner of its recession. 



T^Hien the Glacial period in North America was ending, as soon as the 

 border of the ice had receded beyond the watershed dividing the basins of 

 the j\Iinnesota and Red rivers, it is e^-ident that a lake, fed by the glacial 

 melting, stood at the foot of the ice fields and extended northward as they 

 withdi-ew along the Red River Valley to Lake Winnipeg, filling this \alley 

 to the height of the lowest point over which an outlet could be found. 

 Until the ice ban-ier was so far melted upon the area between Lake 

 Winnipeg and Hudson Bay that this glacial lake began to be discharged 

 northeastward, its outlet was along the present course of the Minnesota 

 River. Because of its relation to the retreating continental ice-sheet, this 

 lake has been named in memory of Prof. Louis Agassiz, the first prominent 

 advocate of the theory that the di-ift was prodviced by land ice.^ Within 

 the past fifteen years the truth of this explanation of the drift has been 

 demonstrated by the recognition and detailed study of the morainic 

 deposits that were accumulated along the boundary of the ice-sheet from 



> A. H. Hansen, in Nature, Vol. XXXIII, 1886, pp. 268, 269, 365. 



= T. F. Jamieson, in Quart. .Jour. Geol. Soc, Vol. XLVIII, 1892, pp. 5-28. 



'Geol. and Nat. Hist. Survey of Minnesota, Eightli Annual Report, for the year 1879, pp. 84, 85. 

 (Jean Louis Rodolphe Agassiz was born in Motier, Switzerland, May 28, 1807, and died in Cambridge, 

 Mass., December 14, 1873. His observiitions of the Swiss glaciers and his principal writings concerning 

 them and the glacial origin of the drift were during the years 1836 to 1846. In the autumn of 1846 

 Agassiz came to the United States, and the remainder of his life was mostly spent here in zoological 

 researches and in teaching in Harvard College, where he founded the Museum of Comparative 

 Zoology. The interests of science in this country were inestimably advanced by his great influence 

 as a teacher and by his extensive writings in zoology, in which and the care of the museum his work 

 has been ably continued by his son, Alexander Agassiz. See the biography, Louis Agassiz: His Life 

 and Correspondence, edited by Elizabeth Cary Agassiz. 2 vols. 1885.) 



