34 Cincinnati Society of HSfatural Hislorij. 



In October, 1860, Prof. G. C. Swallow (Trans. St. Louis Acad. Science, 

 vol, 2) read a paper, entitled " Descriptions of some new Fossils from the 

 Carboniferous and Devonian Rocks of Missouri," in which he described 

 Terebratula arcuata and Natica chesterensis from the Kaskaskia 

 Limestone in St. Genevieve county, Missouri, and at Chester, Illinois, 

 and Allorisma antiqua, which he said was common in the Kaskaskia 

 limestone in Illinois and Missouri. 



We have, therefore, in a periodof eight years, from 1852 to I860,, a 

 description of the distribution and extent of the Kaskaskia limestone, 

 and the definition and illustration of numerous fossils which character- 

 ize it, by Dr. Geo. G. and Dr. B. F. Shumard, Prof James Half, and 

 Prof, G. C. Swallow, appearing in such standard scientific publications 

 as the Exploration of the Red River of Louisiana, the Transactions 

 of the Albany Institute, the Geological Survey of Iowa, and the Trans- 

 actions of the St. Louis Academy of Sciences. 



In 1866, the State Geologist of Illinois (Geo. Sur. of 111., vol. 1) 

 said : 



'• In the spring of 185.3, while acting as Assistant Geologist in the 

 Illinois survey, I was directed by Dr. Norwood, at that time the State 

 Geologist, to go to Randolph county and determine, if possible, the 

 relative position of the St. Louis limestone, and the beds forming the 

 river bluffs at Chester;, and it is, perhaps, proper to state that up to 

 that time the former were supposed to overlie the latter beds. 



*' At Prairie du Rocher, in the northern part of the county, I found 

 the St. Louis limestone in situ, forming the entire blutf, and two miles 

 below I saw this limestone passing under a massive brown sandstone, 

 more than a hundred feet in thickness. Six miles below Prairie du 

 Rocher, this sandstone also passed below the surface, and was suc- 

 ceeded by another limestone formation, which was traced continuously 

 to Chester, and from there south along the river bluffs into Jackson 

 county, where it was overlaid by the sandstones that form the base of 

 the coal measures. I returned to New Harmony, Indiana, the head- 

 quarters of the survey' at that time, and communicated the results to 

 Dr. Norwood, with a copy of my notes and a section, in which I desig- 

 nated the beds at Chester as the Chester limestone. He expressed 

 some doubts as to the correctness of the conclusions to which I had 

 arrived, because the}' conflicted with the views of most western geolo- 

 gists, especially those of Missouri, and he proposed going over the 

 ground with me, for the purpose of reviewing the section I had made. 

 Accordingly in the autumn of the samej^ear I revisited that region, in 

 company with Dr, Norwood, and we retraced the bluffs from the Big 



