H. F. Bain — Limestone at Bethany, Missouri. 437 



P. longispinus Sowerby. 



P. cora D'Orbigny = P. praitenianus of authors. 



Athyris (Seminula) subtilita Hall. 



Hustedia mormoni Marco u. 



Spirifer cameratus Morton. 



ISpiriferina kentuckensis Slmm. 



Allorisma subcuneatum M. & H. 



Chonetes verneulianus N. & P. is somewhat common in No. 

 9 but is very rare in the other members of the section. Spi- 

 rifer cameratus and Productus longispinus are most abundant 

 near the base of No. 4, while Productus costatus and Athyris 

 subtilita are more common in the upper layers. All the species 

 enumerated, however, with the exception of Allorisma sub- 

 cuneatum, range through all the beds making up No. 4. 



The best exposures of the Bethany limestone in southern 

 Iowa are found along Grand River and its tributaries. From 

 the outcrops found there a complete section can be made from 

 the Fragmental limestone at the base up to and above the beds 

 which farther north have been called the Fusulina limestone, 

 but which from their excellent development in that vicinity 

 may now perhaps be best called the De Kalb limestone. 



In Union County there is an important bed of limestone 

 which from the fact that it is well shown on Sand Creek, near 

 Westerville, may be called the Westerville limestone. It lies 

 some little distance above the De Kalb horizon. In Jones 

 township section 28, and farther south along the river, the 

 beds are exposed, showing the following section : 



5. Limestone, ash gray, fine-grained, thin-bedded, becoming 

 almost shaly at the top, with Productus cora, Productus 

 costatus, Spirifer cameratus, Athyris subtilita, Chonetes 

 verneulianus cf. glabra, Lopophyllum proliferum, Straph- 



arollus subquadratus and Fenestelloid bryozoa 10 



4. Shale, gray, calcareous, with thin nodular bands of lime- 

 stone 4 



3. Shale, drab to black . 10 



2. Limestone, impure nodular in two bands 2\ 



1. Shale, drab to black, well exposed at Westerville 8 



These beds extend into Decatur County, being seen near 

 Westerville on Sand Creek and on Grand River. It seems prob- 

 able that the shale (No. 1) extends down to the top of the 

 De Kalb or Fusulina limestone, which is exposed near Grand 

 River and was at one time quarried at the old Madarasz quarry 

 (Sec. 36, Tp. 70, W., R. xxvii W.). The best exposures of the 

 latter limestone and the ones which may be taken as typical 

 are found a short distance east of De Kalb station (Sec. 28, 

 Tp. 70 N., R. xxvi W.). The section at this point is given 

 below. 



