226 



LIFE OF THE PLEISTOCENE 



Terrestrial species 

 Polygyra (fragments) Zonitoidcs arborea 



Pyramidula altemata Bifidaria armifera 



" cronkhitei anthonyi Succinea ovalis 



Vallonia gracilicosla " mar a 



Vitrea hammonis " retusa 



The molluscan remains were found chiefly in the finer sands, showing that 

 they lived in comparatively quiet water. Exceptionally, odd valves of Sphae- 

 rium and fragments of Unios were found in gravel. The terrestrial mollusks 

 in the above list were swept into the river by floods or winds, as happens today 

 in similar situations in Iowa and other parts of the glaciated territory 





VERTEBRATA 





Pisces 





Small vertebra of a fish 









Mammalia 



Mammut americanum 





Camelus species 



" progenhtm 





Camelops kansanus? 



Rhabdobunus mirificus 





Mylohyns? temerarius 



Elepkas columbi 





Megalonyx leidyi? 



" primi genius 





Mylodon harlani? 



" imperator 





A Ices shimeki 



Equus laurentius 





Aftanius calvini 



" complicalus 





Bison, cf. alleni 



" niobrarensis 





Castor canadensis 



" excelsns 





Castoroides ohioensis 



TAeohipparion gratum 





Ursus americanus 



The bones of these animals are for the most part isolated and in some cases 

 fragmentary, and evidently belonged to animals which had died either in a 

 river or had been washed into a river and the bones separated from the body 

 as it decomposed, either lying upon a sand bar or caught in rubbish along the 

 shore. In Harrison and Monona counties the vertebrate (as well as other) 

 remains have been found in sand and gravel pits, of which those listed below 

 are the most noteworthy. 



Harrison County 

 Cox pit, Missouri Valley 

 Payton gravel pit, Pisgah 

 McGavern and Robinson pits 

 Sol Smith Lake 

 Logan, Rodney, and Woodbine 



Monona County 

 Wilkinson and Griffin wells 

 Hawthorn pit, Mapleton 

 Elliott pit, Turin 

 McCleary pit 

 Castanea 



Shimek 8 refers to a somewhat doubtful section in Snyders Hollow, Harrison 

 County, which is characterized at the base by a deposit of interstratified black 



• Geol. Iowa, XX, pp. 365-366. 



