THE KIMMSWICK AND PLATTIN LIMESTONES 
185 
trices are shown to suggest that they may belong to different 
horizons. Of the new species and varieties described by Bran- 
son from the Auburn chert, only Parallelodus oUiquus and Pter- 
ygometopus Uncolnensis have been identified more or less doubt- 
fully from the Plattin of Ralls County. 
Faunal lists 
In the accompanying faunal lists all that is known at present 
of the faunas of the Kimmswick limestone south of Thebes, in 
Illinois and in Ralls and Pike Counties, in northeastern Missouri, 
has been tabulated in order to show the similarity of the Thebes 
fauna to the fauna of the lower part of the Ralls County section. 
On the other hand the fauna of the top of the Plattin limestone 
in Ralls County and that from the Auburn chert has been tabu- 
lated in order to make evident certain differences in faunal 
content. 
In the list of fossils from Thebes, the thickness of the strata 
is indicated in feet and inches; in the list of fossils from Sanders 
branch, the estimates are in feet. In the Sanders Branch sec- 
tion, horizons 1 to 4 correspond to horizons a to f in the Thebes 
section. Horizons j to o of the Thebes section contain about 
the same fauna as the underlying horizons of this section. The 
column marked L. R. records the species found on Little Rock 
Island, which is located about 2 miles north of Thebes. Hori- 
zons 5 and 6 of the Sanders Branch section form the McCune 
zone of the Kimmswick and are not represented in the Thebes 
section. In table 14, exposures corresponding to the lower 
half of the Sanders Branch section are printed on the left side 
of the Sanders Branch section, while exposures corresponding 
to the upper half of the latter are printed on the right. The 
Pike county sections are separated from the Ralls county sec- 
tions by a darker line. 
The numbers preceding the names of some of the fossils in the 
various lists indicate the order in which these fossils are discussed 
in the Description of Species, at the end of this paper. 
