124 KANSAS ACADEMY OF SCIENCE. 



LIST OF FOSSIL PLANTS COLLECTED IN THE VICINITY 



OF ONAGA, KAN. 



By F. F. CKEVECfECE, Onaga, Kan. 

 Read ( by title ) before the Academy, at Topeka, January 2, 1903. 



A S a list of fossil plants without any information as to the horizon 

 -^^^ from which they were collected would be of but little value, the 

 following geological notes are submitted. 



Accepting the Cottonwood Falls limestone as the dividing line 

 separating the Permian from the Carboniferous, we have in Mill Creek 

 township, in which the town of Onaga is situated, only the outcrops 

 of the highest horizons of the latter formation. The Vermillion river 

 with its tributaries has cut a deep trench from north to south through 

 near the middle of the township and removed all trace of the Cotton- 

 wood Falls series of limestone from within the township, but the latter 

 outcrops near by, in the next township west (Lone Tree), and a 

 remnant remains on the hill in Lincoln township, about twenty rods 

 east of the southeast corner of Mill Creek township. 



The Eskridge shale, the highest series of the Carboniferous, with 

 its underlying Neva limestone, exist only as remnants in the north- 

 east and southeast corners of the township. 



Below the Neva limestone, as measured in a section (fig. 1 ), along 

 the south side of the southeast quarter of section 2, township 6, range 

 11, there exists a series of yellowish, ferruginous shales of a thickness 

 of forty-five feet eight inches. This is 10 in figure 1, and is the hori- 

 zon bearing the fossil plants so far collected. 



Next below this is a limestone (9 in our section), consisting of two 

 layers each nine inches thick. The upper layer weathers into whitish 

 angular fragments, which once seen are easily recognized, and forms a 

 horizon easily traced and from which others may be identified. Be- 

 low this limestone is a stratum of dark blue shale eleven and one- 

 half feet thick. This shale ( No. 8 ) becomes much lighter colored 

 by exposure. 



Next below this shale occurs a series of limestones ( No. 7 ) which, 

 from an economical standpoint, we consider worthy of a designation, 

 and from its occurring over most of the township and within the 

 limits of the town of Onaga, where it has been extensively quarried 

 for material of which some of the town's most substantial buildings 

 have been built, we propose the name Onaga limestone. This, like 

 the Neva limestone above, outcrops in bold bluffs, and consists of four 

 layers. The first, or highest one, is a brown-colored stone five inches 



