CHAPTER I 



HISTORICAL REVIEW 



I. General Statement 



The evidences of abandoned shore lines surrounding the Great Lakes were 

 recognized by geologists at an early date. Colonel Charles Whittlesey, 1 as 

 early as 1838, reported a line of beaches on the south shore of Lake Erie; Mr. 

 Bela Hubbard 2 described a beach north of Lake Erie; Mr. James Hall 3 recog- 

 nized the shore of glacial Lake Iroquois in the northwestern part of New York, 

 and Mr. Charles U. Shepard 5 described the ancient lake beaches near Chicago 

 but did not refer them to the agency of glacial formed lakes. These geologists 

 realized that these old beach lines once formed the margins of large lakes, 

 which were the predecessors of the existing Great Lake system. References 

 to the life which peopled the waters of these ancient lakes are rare in early 

 geological works, tho Hall 4 records the presence of Unios and drift wood in the 

 sands of the "ridge road," in northern New York, but gives no detailed ac- 

 count of the species represented. 



For the past fifty years or more, data have been accumulating bearing on 

 the biota of these ancient lakes, until at the present time a varied fauna and 

 flora has been cataloged. The earliest fauna is found (as would be expected) 

 in the sedimentary strata of the first body of water to appear, glacial Lake 

 Chicago, the precursor of Lake Michigan, and it is to the life of this early water 

 body that attention is to be especially directed. Before proceeding to discuss 

 these deposits in detail, it will be of value and interest to review briefly the 

 work of previous investigators. 



II. Previous Records of Life 



1868 bannister. 6 — One of the first investigators to recognize the ancient 

 bay or lake and its southwestern outlet was Henry M. Bannister. The pres- 

 ence of life in the old lake deposits is apparently first mentioned by this author. 



1 Geological Survey of Ohio, 2nd An. Rep., p. 55, 1838. 



1 Geological Survey of Michigan, 3rd An. Rep., p. 104, 1840. 



3 New York Geological Survey, 2nd An. Rep., p. 310, 1838. 



4 Natural History of New York, part IV, Geology of 4th District, p. 348, 1843. 

 6 Amer. Journ. Sci., (i) XXXIV, pp. 134-137, 1838. 



• Geol. of Illinois, III, pp. 241-242, 1868. In this chapter only those works are included 

 which refer specifically to the life of Lake Chicago or its beaches. The records of life outside 

 this area will be found in a subsequent chapter. 



