170 The American Geologist. September, 1897 
taken as a whole. Heretofore little or no mention has been 
made concerning the exact horizons of the fossils in question, 
mere reference to the "Lithograpliic" limestone or "Kinder- 
hook beds" being considered sufficient. Lately, however, ex- 
tensive collections of fossils have been made at all three places 
mentioned, as well as at man}' neighboring localities. Every- 
wlierfe the Lithographic, or Louisiana, limestone has been 
found to be essentially devoid of organic remains, except an 
occasional form in the thin sand}^ partings above tlie bottom 
layer, which is less than one foot in thickness. At the very 
base of the limestone is a thin seam of bult", sandy shale, sel- 
dom over three or four inches in thickness. This seam is 
highly fossiliferous. It contains the Productella pyxidatd 
(Hall), Cyrtina aciitirostris (Shumard), Chonetes ornata 
(Shumard), Sp/rifer kannihalensis (Shumard), and a host of 
other forms, many indistinguishable from species occurring 
in undoubted beds of the Western Hamilton. 
When this phase of the problem arose, as elsewhere present- 
ed, it appeared that, lithologically, the thin, sandy laj-er was 
more closely related to the underlying shales than to the over- 
lying limestone; that faunally, it had very much clearer 
affinities with the Western Hamilton (Devonian) than with 
the ''Kinderhook" (Lower Carboniferous). In Iowa the "De- 
vonian aspect" of the Kinderiiook faunas disappeared, largely,, 
upon Calvin's recent discovery that the "Chemung" sandstones 
of Pine creek, in Muscatine county, Iowa, were in reality true 
Devonian. In Missouri the same Devonian facies of the fauna 
contained in the lowest member of the recognized Carbonifer- 
ous was removed almost completely, by casting out the spe- 
cies found in the thin sandy seam at the base of the Litho- 
graphic limestone. The faunas of the Devonian and Carbon- 
iferous of the upper Mississippi valley thus became more 
sharply contrasted than ever. The apparent mingling of 
faunas from the two geographical sections manifestly had 
been based upon erfoneous assumptions rather than upon the 
detailed field evidence. It was stated* at the time that after 
eliminating from "the Lithographic limestone, the extensive 
fauna commonly ascribed to it, and which came only from a 
thin seam lying below the calcareous member, its real geolog- 
*Iovva Geol. Sur.. vol. i, p. 53, 1893. 
