PLEISTOCENE MOLLUSCA FROM INDIANA AND OHIO^ 



FRANK COLLINS BAKER 

 Curator, Museum of Natural History, University of Illinois 



Two very interesting and valuable collections of Pleistocene 

 material have recently been placed in the hands of the writer for 

 study. These contain a number of species not previously reported 

 from fossiliferous beds, which add largely to our knowledge of the 

 distribution of this group of animals during the great Ice Age. 

 These deposits will be discussed separately and their biotic content 

 compared. 



I am indebted to Dr. Morris M. Leighton, of the department 

 of geology, University of Illinois, for the opportunity of studying 

 the Ohio deposit, and to Rev. W. H. Fluck, of Hope, Indiana, 

 for the material from the Indiana deposit. The following gentle- 

 men have examined critical material and to them my thanks are 

 due: Dr. H. A. Pilsbry, Academy of Natural Sciences, Philadelphia, 

 Amnicolidae; Dr. V. Sterki, New Philadelphia, Ohio, Sphaeriidae; 

 Dr. Bryant Walker, Detroit, Michigan, Amnicolidae and Physa; 

 and Mr. Calvin Goodrich, Pleuroceridae. 



THE OHIO DEPOSIT 



The material from Ohio occurs in extensive marl beds at the 

 south end of Rush Lake, Logan County. Dr. M. M. Leighton, 

 who collected the material, thus describes the deposit: 



The exposure occurs in an artificial ditch which drains into the lake from 

 the south. The beds begin close to the lake and run south for a hundred yards 

 or more. The farm land immediately to the east shows great numbers of these 

 shells mixed in with the soil. The exposure is about six feet deep, and the 

 shells make up whole beds of lenticular shape, interbedded with clay strata, 

 in some of which are a few scattered sheUs. Some of the shell beds are as much 

 as ten inches thick. The interbedded clay shows no lamination and is dark in 

 color. I do not believe there is any question about their being post-Wisconsin 

 in age, but on the other hand they do not seem to be extremely recent. 



' Contribution from the Museum of Natural History, University of Illinois, No. 9. 



439 



