j OS The American Geologist. August, 1905 
tologist as it places the great fossil horizon at Grand Summit 
iti the Garrison formation instead of in the Permian. 
The horizon of the Cottonwood limestone can not be 
located with certainty, but it may be near number 9 of our 
section. 
The appearance of the exposure of the lower Wreford 
limestone in the cut east of Dexter, Cowley county, is typical 
of its southern extension, showing well the imperfectly silici- 
fied limestone, "sandstones" of the inhabitants, and heavy 
chert layers. In this region local structure becomes a factor 
in studying the stratigraphy of these rocks. The writer 
hopes to be able to complete the study of the stratigraphy 
of his county the coming season. In the mean time, how- 
ever, it is well to correct the section of the bluffs north of 
Arkansas City, measured by Beede in the summer of 1896. 
This section was measured in the evening at a bad exposure 
and further study of better exposures gives the following sec- 
tion. The first section was published by Prosser.* 
SECTION OF BLUFF NORTH OF ARKANSAS CITY. 
12. Limestone, fossiliferous, porous 10 ft. inches 
11. Shales, yellow calcareous 2 " 6 " 
10. Limestone, rotten clayey 3 " " 
9. Yellow shales 2 " 
8. Covered 2 " 
7. Limestone 1 " 8 " 
*6. Shale, yellow 5 " 
5. Shale, blue and green" 15 " " 
4. Limestone " 4 " 
3. Covered 7 " " 
-2. Limestone 1± " " 
1. Covered to level of bottom land 10 " " 
Total 59 ft. inches 
Prosser 1 " was inclined to refer this section to the Marion 
formation and the exposure on the opposite side of the Wal- 
nut river, east of the Santa Fe depot, to the Winfield forma- 
tion. However, in the light of the better section and the 
concretions on the ground, on the bluffs north of the city, 
it seems seems probable that number 6 of this section is the 
* Op. cit. p. 174. 
t Op. cit. p. 174. 
