348 



LIFE OF THE PLEISTOCENE 



Vertigo modesta 

 Cochlicopa lubrica 

 Vitrca hammonis 

 Euconidus julvus 



Succinea obliqua 

 Helicina occulta 

 Eggs of small snails 





One of the best eastern loess sections at present known is to be found in and 

 about Iowa City, Johnson County. Both post-Kansan and Post-Iowan loesses 

 occur (the former bluish, the latter yellowish) and both are fossiliferous, the 

 species being the same in both horizons, according to Shimek. The species 

 noted below have been identified from post-Iowan loess: 13 



Galba caperata 



" humilis modicella 

 " obrussa 

 Helicina occulta 

 Succinea avara 



" grosvenori 



" obliqua ( = ovalis) 

 Vallonia gracilicosta 

 Bifidaria armijera 



" pentodon 

 Vertigo ovata 

 Pupilla blandi 



" muscorum 

 Cochlicopa lubrica 



Zonitoides minusada 

 Euconulus julvus 

 Vitrca indentata 

 " hammonis 

 Helicodiscus parallelus 

 Pyramidida cronkhitei anthonyi 



perspectha 



shimekii 



alternala 

 Sphyradium edentulum alticola 

 Oreohelix iowensis 

 Polygyra projunda 



" multilineata (small form) 



Beyer 1 ' records loess fossils from two localities in Marshall County, from 

 the upper portions of the deposits, which are probably to be correlated with 

 the post-Iowan loess. 



(1). Two miles west of Marshalltown. 

 Succinea avara Vallonia pidchella (probably gracilicosta) 



" obliqua Pupilla muscorum 



Pyramidida shimekii Bifidaria pentodon 



cronkhitei anthonyi Sphyradium edentidum alticola 



Euconulus julvus 



(2). One half mile south of Bangor. 

 Succinea avara Pupilla muscorum 



Bifidaria pentodon Helicodiscus parallelus 



a. Vertebrate fossils 

 Proboscidian remains have been observed in various parts of Iowa in situa- 

 tions possibly referable to the post-Iowan interval. Only a few of the observed 

 records, however, appear definite enough to include in the Peorian interval. 

 Two of these are in Linn County. 15 



18 Shimek, Amer. Geol., XXVIII, p. 345. 



" Geol. Iowa, VII, p. 237. 



16 Anderson, Augustana Lib. Pub., V, pp. 28, 29. 



