LATE CENOZOIC GASTROPODS 



23 



1937. Pleistocene land and fresh-water Mollusca 

 as indicators of time and ecological condi- 

 tions: in Early Man, George Grant Mac- 

 Curdy, ed., J. B. Lippincott Co., Philadelphia, 

 p. 67-74. 



1938. New land and fresh-water Mollusca from the 

 upper Pliocene of Kansas and a new species of 

 Gyraulus from early Pleistocene strata: Nau- 

 tilus, v. 51, no. 4, p. 126-131. 



1939. Fieldbook of Illinois land snails: Illinois Nat. 

 Hist. Survey Manual 2. 



1940. A new Helisoma from the Pliocene of Florida: 

 Nautilus, v. 54, no. 1, p. 17. 



1942. A new Gyraulus from the Pleistocene of Cali- 

 fornia and a new Parapholyx from a supposed 

 Pliocene deposit in Oregon: Nautilus, v. 55, 

 no. 4, p. 130-132. 



1943. Mollusca contained in the test pit deposits: 

 Carnegie Inst. Washington Pub. 538, p. 117- 

 119. 



1945. The molluscan family Planorbidae: Univ. 

 Illinois Press, Urbana. 



