28 
IOWA ACADEMY OP SCIENCES. 
Marion and Pike counties, Missouri, at Hannibal, Louisiana and Clarks- 
ville principally, were the leading localities for a large proportion of the 
“Kinderhook ” fossils originally described by Shumard, Hall, White, and 
Winchell. Most of these forms have a very decided Devonian aspect which 
gives a peculiar and characteristic physiognomy to the faunas of the three 
beds. Heretofore little mention has been made concerning the exact 
horizon of the fossils in question, mere reference to the “ Lithographic ” 
limestone, or Kinderhook bids, being considered sufficient. Lately, how- 
ever, extensive collections of fossils have been made at all three places 
just mentioned, as well as many intervening and neighboring exposures. 
Everywhere the Lithographic, or Louisiana limestone has been found to be 
essentially devoidi of organic remains, except an occasional form in the 
thin sandy partings above the bottommost layer, which is less than one 
foot in thickness. At the very base of the limestone is a thin seam of buff, 
sandy shale, seldom over three or four inches in thickness. This seam is 
highly fossiliferous. It contains the Productella pyxidata (Hall), Cyrtina 
aeutirostris (Shumard), Chonetes ornata (Shumard), Spirifera barmibalensis 
(Shumard), and a host of other forms, many indistinguishable from species 
occurring in undoubted beds of the western Hamilton. 
Lithologically, the thin sandy layer is more closely related to the under- 
lying shales than with the overlying limestone. Faunally, it has very 
much nearer affinities with the western Hamilton (Devonian) than with 
the Kinderhook (Lower Carboniferous). In Iowa the “Devonian aspect” 
of the Kinderhook faunas has disappeared largely, since Calvin’s recent 
discovery that the “ Chemung ” sandstones of Pine creek, in Muscatine 
county, Iowa, are in reality true Devonian. In Missouri the same Devonian 
facies of the fauna contained in the lowest member of the Carboniferous is 
lost from view, almost completely, by eliminating the species found in the 
thin sandy seam at the base of the Louisiana or lithographic limestone. 
The faunas of the Devonian and Carboniferous of the upper Mississippi val- 
ley thus become more sharply contrasted than ever. The apparent min- 
gling of faunas from the two geological sections, manifestly was based upon 
erroneous assumptions rather than upon the detailed field evidence. 
Depriving the “ Lithographic” limestone, almost entirely of the exten- 
sive fauna commonly ascribed to it, and which, as has been seen, comes 
from a thin seam lying below the calcareous layers its geological age be- 
comes a problem yet to be solved. The few fossils known from the lime- 
stone itself have, been heretofore rarely met with. It is not at all unlikely 
that the lower limestone of the Kinderhook eventually may prove to be of 
Devonian age. But until abundant evidence to this effect is found, it seems 
advisable to still consider the Louisana (Lithographic) limestone as the 
basal member of the Carboniferous. 
Since these remarks were made the organic remains which 
were found only in the thin basal shale (No. 6) have been 
obtained from higher levels, as is clearly brought out in the 
accompanying table. The whole formation is thus more closely 
related to the strata below than those above. 
The Hannibal shales (Nos. 10 and 11) are almost wholly 
devoid of fossils in Missouri, but farther north, at Burlington, 
