252 



LIFE OF THE PLEISTOCENE 



However, it has not been thot necessary to change any of the statements or lists 

 of loess fossils appearing under the Yarmouth or Sangamon Interglacial inter- 

 vals in this work. The transfer of some of these records to the Peorian interval 

 would not materially affect the general discussion of the life of the Pleistocene 

 Period. 



At Iowa City, Johnson County, a Kansan loess occurs beneath an Iowan 

 loess; a section given by Webster 25 is reproduced below: 



1. Very fine brownish "loamy" soil 3 inches 



2. Very fine and homogeneous yellowish-clayey earth (Iowanloess) 15 feet. 



3. Very fine and homogeneous bluish-gray clayey earth, with fossils (Kansan loess) 5 feet. 



The following fossils have been identified from the Kansan loess: 26 





Old name 

 Zonites viridulus 



" limatidus 



" fulvus 

 Patula strigosa 



" strialella 

 Ferrusacia subcylindrica 

 Pupa muscorum 



" blandi 

 Vertigo simplex 

 Mesodon multilincata 

 Vallonia pulchella 

 Succinea avara 



" var. vermcta 



" obliqua 

 Helicina occulta 

 Limnaea desidiosa 

 Physa species 

 Pisidium species 

 Egg shell of small helix 



Modern name 

 Vitrea hammonis 

 Pyramidula shimekii 

 Euconulus fulvus 

 Oreohelix iowensis 

 Pyramidula cronkhitei anthonyi 

 Cochlicopa lubrica 

 Pupilla muscorum 



" blandi 

 Sphyradmm cdentulum alticola 

 Polygyra nudtilineala 

 Vallonia gracilicosta 

 Succinea avara 



" grosvenori? 



" obliqua 

 Helicina occulta 

 Galba obrussa 

 Physa gyrina 

 Pisidium species 



Shimek 27 has published several lists of the mollusks of the loess of Iowa 

 City. These lists do not separate the faunas of the post-Kansan and post- 

 lowan loeses; the statement is made however, that they both contain practically 

 the same species. The species not listed by Webster are tabulated below: 



Bifidaria armifera 

 ' ' penlodon 

 Vertigo ovata 

 Vitrea indentata 

 Zonitoides minuscula 



Pyramidula perspectiva 



" altemata 

 Helicodiscus parallelus 

 Succinea species 

 Galba caperala 



26 Amer. Nat, XXII, pp. 417-419. 



™Op.cit.,p. 119. 



» Amer. Geol., I, pp. 149-152; XXVIII, p. 345. 



