r 



y 



o ' 



■ r 



'^ Notes on the Cretaceous Flora of 

 Western Iowa. 



By PAUL BARTSCH. 



A YEAR ago I received from the State University for iden- 

 tification a quantit}- of material containing fossil leaves. The 

 rock containing the fossils is a very hard ferruginous aren- 

 aceous shale, belonging to the Dakota group of the Creta- 

 ceous strata. It was taken from the Ilolman Cut, Woodbury 

 Co., NE. qr., Sec. 30, Twp. 88, R. ^7. 



Mr. Bain gives the following table of the strata in the locality 

 concerned: 



12 Loess with some concretions ....... 20 feet 



II Sandstone, yellow to white . 20 " 



10 Shale, lignite in part ........ i^4 " 



9 " white to yellow or gray ....... 4 " 



8 " d.irk gray, argillaceous ...... 3 " 



7 " white, very silicious ....... 2 " 



6 " dark gray ......... 2 " 



5 " gray to yellow . . . • . . . 10 " 



4 " black to gray . . . . . . . . i)4 " 



3 " grayish yellow with ferruginous disseminations . . 2 " 



2 " tire clay .......... 8 " 



I " gray to yellow, iron stained . . . . . . 10 " 



Number 5, he continues "bears a great many crystals of 

 selenite, also large ferruginous boulders of sandstone in which 

 numerous imprints of Dakota leaves are imbedded." 



The mode of occurrence of these leaves is somewhat vari- 

 able. At times they appear horizontally flattened, parallel to 

 the plane of deposition. Then again we find them bent, 

 twisted, torn, ami mixed up in general confusion. 



Occasionally the rock seems composed entirely of fossil 

 178 



