260 T. W. STANTON DAKOTA SANDSTONE PROBLEMS 



conspicuous sandstones to a position near the top of the Dakota. For 

 convenience of reference his lists may he repeated here, as follows : 

 From thin sandstone layers of first shale bed : 



Corbicula subtrigonalis Meek. 



Trif/onan-a salinaensis Meek. 



Vol din microdonta Meek. 



Crassatellina oblong a Meek. 

 *Arcopagella macrodonta Meek. 



Tellina substitute Meek. 



Protocardia salinaensis Meek. 



Cardium kansasense Meek. 

 *Cyrena dakotensis (Meek and Hayden). 

 *Margaritana nebrascensis Meek. 

 *Mactra siouxensis Meek and Hayden. 

 * Tellina modest a Meek. 



From fossil bed in saliferous shale : 



Leptiosolen oonrudi Meek. 

 *Pharella dakotensis Meek and Haydeii. 



Cardium kansasense Meek. 



In 1906 the localities near Beloit and Denmark, Kansas, were visited 

 by me for the purpose of studying the marine horizon discovered by 

 Logan at the top of the Dakota. At Beloit the following forms were col- 

 lected : 



Ostrea sp. Large simple form. 



Anomia sp. 



Modiolus sp. Related to M. filisculptus Cragin. 



Gervillia sp. 



T rigonarca siouxensis Hall and Meek. 



Cyrenaf sp. Resembles C. dakotensis Meek. 



Tellina sp. 



Corbula hicksii White. 



Corbula sp. 



Anatina sp. 



I*svnd(»nelania? sp. 



inch ura sp. 



Approximately the same horizon in the coal mine shafts two miles 

 north of Denmark, Kansas, yielded the following : 



Ostrea sp. Small simple form. 



Anomia sp. 



Modiolus sp. Related to M. filisculptus Cragin. 



Area sp. 



Anatina sp. Same as at Beloit. 



* These species are not known in the Mentor fauna and are probably incorrectly 

 identified. 



