Geological Papers. 81 



miles long. In the northeast quarter of section 5 a small patch of 

 Cottonwood limestone is found. To follow the limestone across 

 this plane is again quite difficult. Only the harder part of the 

 stratum is left, on account of the erosion having been very slow. 



Here again one must rely largely upon the formation above and 

 below in order to follow the Cottonwood. Near the section line of 

 section 8, township 22, range 10, is a long, very gently sloping 

 ridge. On the highest part near the east line, say one-fourth of a 

 mile from the east line, occurs the Cottonwood limestone; but only 

 a few acres, at most, and in a very narrow line. The ridge is cov- 

 ered by chert, the limestone being mostly gone. More chert seems 

 to be here in the upper half of the limestone. No solid limestone 

 that contains Fusulina is seen for many miles to the north. The 

 upper and middle Neva limestones have changed in their outcrop 

 from what they were to the north. 



About the center of section 18, township 22, range 10, a large 

 cliff gives a good exposure of Cottonwood limestone, and here the 

 formation is only about two and one-half feet thick, blue in color 

 instead of yellow, but with the texture of the Cottonwood line. 

 Chert is seen in all parts of the formation. The Fusulina part 

 seems to be nothing but shale. The fauna of the Florena shales is 

 nicely seen here. The line at the top of the Florena shales is quite 

 hard, while in appearance it resembles the lower Neva, except 

 s Dme very large moUuscan shells are found in it. This stratum is 

 thick enough to make a good escarpment for some six or eight miles 

 north of this point. The escarpment around the two branches of 

 the Verdigris may be easily followed, but it is quite difficult to 

 cross the divides, because here the land lies in the form of a plane, 

 and when the formation is seen, on account of the very slow 

 weathering and- erosion only the hardest and most irregular parts 

 of it are left. The appearance of the land is such as to deceive one 

 greatly. The Cottonwood limestone runs far up on the main 

 escarpment of the Flint Hills, the creeks all having a very great 

 fall; and often just where the limestone crosses a ravine is the 

 only place where you can drive across. The velocity of the water 

 is so great that great quantities of rock are brought down that 

 weigh from a few to 50 or 100 pounds. Often holes are cut out in 

 the bed of the stream where the water pours over the harden lime- 

 stone, and this affords most excellent places to study the recently 

 eroded formations. Often the head of the creek is from one-half 

 mile to a mile above the Cottonwood limestone, and the made land 

 ■covers it near the heads of the creeks in such a way that it is hid- 

 -6 



