40 
PALEOZOIC FAUNAS OF MISSOURI 
for that particular expression of the Lower Carboniferous series, 
which is characteristic of the rocks of the Mississippi valley. 
The “Chouteau group” of Broadhead is already well defined 
and consists of the 
Chouteau Limestone, 
Vermicular Shales and Sandstones, 
Lithographic Limestone, 
of the Missouri reports of Swallow, Shumard and Broadhead. 
The formation c. of my table refers to this Chouteau group 
of Broadhead, called “Chemung group” in the reports of the 
first survey of Missouri by Swallow and Shumard; so called also 
by Mr. Hambach in the list above referred to. 
The Ozark group (d. of my table) is a group proposed to in¬ 
clude the formations heretofore described as Encrinital lime¬ 
stone, Burlington Limestone, Keokuk group, and their equiva¬ 
lents in Missouri, Illinois, and -Iowa, and part if not all of the 
Siliceous group of Tennessee, all the faunas of which indicate a 
close paleontologic relationship. It is possible that some of the 
formations heretofore referred to as the Warsaw group may more 
properly belong to this group. 
The name Ozark group is suggested by the fact of the promi^ 
nent development of the formations constituting the group on the 
southern and western margins of the Ozark uplift. 
The Ste, Genevieve group (E.) is a name and classification 
proposed to include the formations whose faunas have been de¬ 
scribed under the names Warsaw (in part), St. Louis, Chester, 
Kaskaskia, upper Archimedes, Ferruginous Sandstone, and their 
equivalents in Missouri, Illinois and Iowa; and particularly defined 
under the name “Archimedes group” by B. F. Shumard in his 
report on the Geology of Ste. Genevieve County, Missouri.® 
In his classification this group includes “Archimedes Limestone 
or Kaskaskia Limestone, 200 feet; Sandstone, 80 feet; Archi¬ 
medes Limestone, 50 feet; St. Louis Limestone, 150 feet; Oolitic 
Limestone, 20 feet; Archimedes Limestone or Warsaw Limestone, 
80-100 feet.” It is underlain by the “Encrinital Limestone” and 
overlain by the Coal Measures. This group is particularly well 
developed on the eastern and north-eastern margin of the Ozark 
uplift. 
6 Geological Survey of State of Missouri, 1855-1871, pp. 292-293, 1873. 
