3S^ The Ainer'tCiti) Gpohtfl'ixt. December, 1892 
Swallow*, Hullt, and White!, who are all well acquainted with the 
sections and their fossils, correlated the beds immediately below 
the Burlington limestone with the Chemung (Devonian). In 
northeastern Missouri and adjoining portions of Iowa and Illinois, 
the "Chemung" includes the Chouteau limestone. Vermicular 
shales and Lithographic limestone. 
Hall having studied more particularly in Iowa, erroneously re- 
garded certain sand}' shales, or 3'ellow sandstones, just below the 
great limestone tit Burlington, identical in age with a lithologi- 
cally similar rock 50 miles to the northward, at the mouth of 
the Pine creek, Muscatine count3\ The latter has recently been 
shown by CalvinI to belong to the Hamilton group as known in 
Iowa. Consequently Hall having investigated the northern local- 
ity more thoroughl}', perhaps, very naturall}' came to the conclu- 
sion that the entire formation under consideration, as he under- 
stood it, was actually Devonian. But, as already shown, the 
rocks of the two places are widely separated in point of time. 
Meek and Worthen||, who had considered chiefly the fossils in 
the upper part of the so-called "Chemung,"' both at Burlington, 
Iowa, and at Kinderhook, Illinois, a few miles from Hannibal, 
Missouri, regarded the fauna more closely related to the Carbon- 
iferous than to the Devonian. Since the publication of these 
views writers upon the subject have accepted them and they have 
been adopted in the geological reports of Illinois, Missouri and 
Iowa. 
By reference to the vertical section already given it will be seen 
that the commonly known Kinderhook of this region is a three- 
fold division, the upper and lower being limestones and the 
median one a clayey or sandy shale. At Burlington the fossils 
heretofore noted have been found only in the upper portion of the 
formation, though recently an extensive and interesting fauna 
iias been discovered in the claj'ey portion much lower down. 
Here the lower calcareous member is not exposed. At Louisiana 
and the vicinity the median member is practically unfossiliferous; 
as is also the lower, except at the very base. 
*Geol. Sur. Missouri, Ann. Rep., p. 101. (1855.) 
tGeol. Iowa, Vol. i, p. 90. (1858.) 
tProc. Boston Soc. Nat. Hist., Vol. viii, p. 289. (1862.) 
§ American Geologist, Vol. iii,r p. 25. (1889.) 
,11 Am. Jour. ScL, (2), Vol. xxxii, p. 167. ( 1866.) 
