CARB ONIFER OUS A ND PERM I A N FORMA TIONS 7 



Derbya crassa (M. & H.) H. & C. (rr). 



Pinna peracuta Shum. (?) only a fragment (rr). 



Allorisma sp. fragment of an impression (rr). 



Archceocidaris sp. fragment of spines (r). 



Above the Cottonwood limestone in northern and central 

 Kansas are about fourteen feet of yellowish, calcareous shales, 

 the lower seven feet of which contain abundant fossils. In 

 Nebraska no similar shales have been found above the Cotton- 

 wood shales. Perhaps the shaly limestones and shales — Nos. 3 

 and 4 of the above section — represent the Cottonwood shales, 

 although the fossils are not nearly as abundant. If this sup- 

 position be correct, then they belong in the Cottonwood forma- 

 tion Again it is possible that the Cottonwood shales are repre- 

 sented by the thin shale or shaly limestone, No. 3, which is 

 between one and two feet in thickness; while No. 4 represents 

 the shaly limestones at the base of the Neosho formation m 



Kansas.' 



The Gilbert quarry region is six miles west and two and one- 

 fourth miles north of Auburn or about two and one-half miles 

 northwest of the Nemaha county quarry. Near the head of a 

 small stream and by the highway are several quarries. One on 

 the east side of the highway, just south of the Gilbert quarry, 

 gives the following section : 



Feet Feet 



c Coarse grayish shales to rather shaly gray limestone at the 



^' ^^gg . - - - - 3 = io|< 



4. Massive gray limestone, fragments of fossils numerous (2 



feet in Gilbert quarry) - - " ' ' " - lyi - 1 A 



3. Rather coarse, grayish shales (shaly limestone m Gilbert 



quarry) - - - 



2. Cottonwood limestone, massive Fusulina limestone with 



small amount of flint and an occasional critwid segment, and ^^ ^ 



fragment of ^//^J^" - ' ' " ' " - 3/2 — 5 



I. Grayish to slightly buff limestone without /^«^/^/«/a^-. Bot- 



tom of quarry 

 a = abundant ; aa = very abundant ; c = common ; r = rare ; rr = very rare, when but 

 one or two specimens are found. 



' See Journal of Geology, Vol. Ill, 1895, P- 766. 



