KINDERHOOK FORMATION 275 



consideration of the internal deposits. There has, in the last half cen- 

 tury, been so much controversy in regard to the age and distribution of 

 the Kinderhook that we must now look into original meanings before 

 attempting to arrive at our final conclusions. 



Three separate and distinct lines of consideration at the outset arise. 

 They have to do, first, with the stratigraphy ; second, with the faunal 

 features, and, third, with the geological age according to the most ap- 

 proved methods of determination. Each of these phases has its own 

 individuality and requires a perfect independence of treatment. Usually 

 no distinction is made, and therein is the main source of much of the 

 confusion that has arisen in regard to the nature and relations of the 

 Kinderhook. 



OWEN'S SECTION 



As one, after being in the field, passes in review the published data 

 relating to the beds which have given rise to the Kinderhook contro- 

 versy, he can not help looking on many of the points of dispute in a very 

 different light from that in which they were originally presented. 

 Standing now, after an elapse of 60 years, one can not but marvel at the 

 wonderful discernment displayed in the first efforts to differentiate the 

 Carboniferous formations of the Mississippi valley. Time has not 

 dimmed the work of that pioneer in American geology, David Dale 

 Owen, in his discriminations of the Carboniferous limestones of the con- 

 tinental interior.* 



Owen's arrangement of the geological formations of the region rests 

 primarily on lithologic grounds; but fossils received full consideration. 

 So far as it goes, this writer's scheme is essentially the plan now ac- 

 cepted. New titles have displaced the old, but the division lines remain 

 almost unaltered. 



To the shales underlying the Encrinital (Burlington) limestone at the 

 city of Burlington and the city of Hannibal, Owen gave the name 

 "Argillo-calcareous group." Although the nether limit was not specific- 

 ally located, the group is practically coextensive with what was later 

 termed the Hannibal shales. 



HALL'S DETERMINATIONS 



Fresh from the rich paleontologic fields of New York, where a stand- 

 ard Paleozoic section for America had then been but recently established, 

 James Hall was easily led to discover in the rocks of the Mississippi 

 valley the faunal horizons which he knew so well in his own state. In 



*Geol. Survey Wisconsin, Iowa, and Minnesota, 1852, p. 90. 

 XLI— Bull. Geol. Soc. Am., Vol. 13, 1901 



