Dual Character of the Kinderhook Fauna. 169 
neously regarded the sandy shales or yellow sandstones below 
the great limestone at Burlington as identical in age with 
lithologically siuiilar strata 50 miles to the northward, at the 
mouth of Pine creek in Muscatine county. The Fine creek 
rocks have recently been shown by Calvin* to be, beyond all 
doubt, not only not equivalent to the Burlington beds, but not 
(carboniferous at all. As shown by abundant fossils they be- 
long to the Hamilton division of the Devonian as known in 
Iowa. Hall, having investigated this northern localit_y more 
thoroughly, perhaps, and being impressed with a manifestly 
typical Devonian fauna, very naturally came to the conclusion 
that the formations of the two localities being the same, were 
both older than the Carboniferous, whereas they were widely 
separated in point of time. But Meek and Worthen,-]- who 
had considered chiefly the fossils in the upper part of the so- 
called "Chemung,'' both at Burlington, Iowa, and at Kinder- 
hook, Illinois, a few miles from Hannibal, Missouri, regarded 
the fauna contained to be Carboniferous rather than Devon- 
ian, and the whole sequence was accordinglj'^ placed in the 
former. 
Reference to the published vertical sections of the Kinder- 
hook shows that the formation as commonly known in the re- 
gion is a triple division, the upper and lower parts or subdi- 
visions being limestones, and the middle one shale. At Bur- 
lington no fossils heretofore noted have been found except in 
the upper portion of the formation. It has been only very 
recently that an extensive and interesting fauna has been dis- 
covered in the clayey portion much lower down. Here the 
lower calcareous member, if it exists, is not exposed. At 
Louisiana and in the vicinity, the median member has always 
been considered unfossiliferous, as has been also the lower 
limestone except at the very base. Marion and Pike coun- 
ties, Missouri, at Hannibal, Louisiana and Clarkesville prin- 
cipally, were the leading localities for many of the "Kinder- 
hook" fossils originally described by Shumard, Hall, White 
and Winchell. Most of these forms have a most decided De- 
vonian aspect. In consequence a peculiar and characteristic 
phj^siognomy is imparted to the faunas of the three members 
*Amer. Geol., vol. II, p. 25, 1889. 
■fAmer. Jour. Sci., (2), vol. xxxii, p. 1G7, 1866. 
