58 



Trans, Acad. Sci. of St. Louis. 



and the following section given of the rocks at Burlington 

 of the Kinderhook stage, at that time referred to the ** Che- 

 mung Group.''* 



Chemung 

 Group. 



Oolitic bed (often absent) its great- 

 est thickness 4 feet. 



Argillaceous sandstone with fossils 

 as below, of Chemung species. ... 6 feet. 



Limestone, irregularly-bedded, con- 

 cretionary and rarely brecciated, 

 with shaly interlaminations ; com- 

 pact, brittle, ash-colored, appar- 

 ently siliceous. Higher beds more 

 regular and arenaceous; near the 

 base, a thin band of limestone 

 charged with Chonetes 10 feet. 



Fine-grained, siliceous and argillace- 

 ous sandstone, with bands of shale, 

 highly f ossilif erous ; lower half 

 much softer and more argillaceous 

 than the upper part (often shaly). 25 feet. 



Soft green shale like that of Portage 

 group, to level of river 82 feet. 



In 1860 C. A. White published a paper entitled ** Observa- 

 tions upon the Geology and Paleontology at Burlington, Iowa, 

 and its Vicinity "t in which the Kinderhook section at Burling- 

 ton was described, and later, in 1870, while he was State geol- 

 ogist, the section was again described in his official report.! 

 In White's section seven beds were recognized, as follows: — 



7. Impure limestone, sometimes magnesian, passing grad- 

 ually into the Lower Burlington limestone. 3 toj4 

 feet in thickness. 



* Rep. Geol. Surv. Iowa. li:90. (1868.) 



t Jour. Bost. Soc. Nat. Hist. 7 : 209-235. 



X Rep. Geol. Surv. Iowa. 1 : 192-193. (Des Moines, 1870.) 



