4 CHARLES S. PROSSER 



With the exception of the region adjacent to the Missouri 

 River, the geology of Nemaha county was not described by 

 Meek or Hayden. 



About twelve miles northwest of Aspinwall and some 235 

 feet above Nemaha City, which is near the level of the Missouri 

 River, and near the center of Nemaha county, is Auburn, the 

 county seat. To a large extent, the rocks of this region are con- 

 cealed by the thick deposit of loess, but there are occasional 

 exposures along the streams or at favorable places on the bluffs 

 or hills. In the vicinity of Auburn are a few outcrops of rocks 

 which are referred to the upper part of the Wabaunsee forma- 

 tion. Along the highway, one and one-fourth miles directly 

 west of Auburn, the rocks show for a short distance. The top 

 of the outcrop is some thirty-five feet higher than the Auburn 

 hotel, or approximately 270 feet above the Missouri River, and 

 is just west of the Sheridan cemetery on the east side of the South 

 Fork of the Nemaha River. The following beds occur in 

 descending order : 



Feet 

 5. Rough yellowish limestone - - - - - -. - i =65 



4. Soft light gray to yellowish shales - - - - - 2 = 64 



3. Drab hard limestone that weathers to a light gray color. A few 

 fossils — Aviculopecten occidentalis (Shum.) M. & W. and frag- 

 ments of other species - - - - - - - -2^62 



2. Light gray and greenish shales, the lowest very white - [ , , 



I. Covered to the level of South Fork of the Nemaha River - - S 



These rocks are considered to belong in the upper part of 

 the Wabaunsee formation ; for on the upland two and one-half 

 miles farther west and perhaps fifty feet higher is a ledge of light 

 gray limestone composed to a considerable extent of specimens 

 of Fusiilina cylindrica Fischer which the author regards as the 

 Cottonwood limestone of Kansas. There are a number of out- 

 crops and quarries of this limestone on the upland in the western 

 central part of Nemaha county, as well as a few exposures of the 

 underlying rocks, but as they are only a few miles northwest of this 

 eastern outcrop of the Cottonwood limestone they may be 

 described in connection with it. 



