62 FRANK COLLINS BAKER 



Baker, Frank Collins. 



1920&. "The Life of the Pleistocene or Glacial Period," University of 



Illinois Bulletin, Vol. XVII, No. 41, pp. i-xiv, 1-476. 

 1921. "New Forms of Pleistocene Mollusca from Illinois," Nautilus, 



Vol. XXXV, pp. 22-24. 



Chamberlin, T. C, and Salisbury, R. D. 



1888. "Preliminary Paper on the Driftless Area of the Upper Mississippi 

 Valley," U.S. Geological Survey, Annual Report, Vol. VI, pp. 199- 

 322. 



Leverett, Frank. 



1899. "The Illinois Glacial Lobe," U.S. Geological Survey, Monograph 

 38. 



McGee, W. J. 



1 89 1. "The Pleistocene History of Northeastern Iowa," U.S. Geological 

 Survey, Eleventh Annual Report, Part I, pp. 189-577. 



Pilsbry, Henry A. 



1919. Monograph on Pupillidae in Tryon's Manual of Conchology , II, 

 Vol. XXV. 



Shaw, E. W., and Trowbridge, A. C. 



1916. "Galena-Elizabeth Folio, Illinois-Iowa," U.S. Geological Survey, 

 Geological Atlas, No. 200. 



Sterki, Victor. 



1892. Monograph on Vallonia in Tryon's Manual of Conchology, II, Vol. 

 VIII, pp. 247-61. 



1916. "A Preliminary Catalog of the North American Sphaeriidae," 

 Annals, Carnegie Museum, Vol. X, pp. 429-77. 



Wolf, John. 



1870. "Descriptions of Three New Species of Shells," American Journal 

 of Conchology, Vol. V, p. 198. 



