The Tcr))i Augusta in Geology. — Kcyes. 233 
cession containing the beds in question the typical Warsaw is 
carefully excluded and placed in the St. Louis, as was done 
by Worthen and most others. This is most distinctly shown 
by the reference, quoted above, to the "Keokuk group" being 
included in the Osage, for the "Keokuk group" expressly ex- 
cluded the typical Warsaw beds. 
Another important point in the proposal of the term Osage 
and the selection of the name from a locality in southwest 
Missouri was that, owing to the unsatisfactory and indefinite 
character of the then existing literature and notes pertaining 
to that region, there was thought to be a "mingling of faunas of 
both Burlington and Keokuk beds." Later investigation, 
however, has shown that Chouteau and the two limestones al- 
ready mentioned are as sharply contrasted lithologically, faun- 
ally and stratigraphically as along the Mississippi river where 
these formations are typically developed. 
In the prosecution of the geological survey of Missouri the 
Carboniferous deposits were given special stratigraphical at- 
tention. Ihe formations of the Mississippian series (Lower 
Carboniferous) were taken up in particular and traced from the- 
typical localities on the Mississippi river through the central 
into the southwestern part of the state. In the original loca- 
tions in southeastern Iowa, the Lower Burlington, the Upper 
Burlington, the Keokuk, and the W'arsaw (which had been 
generally placed in the St. Louis) were found to contain essen- 
tially the same faunae-, showing a continuous and progressive 
evolution from the base to the top of the sequence. South- 
westwardly, around the Ozark uplift the typical section was 
found as far as the Missouri river, but beyond this point, for 
a distance of over 100 miles, was more or less largely removed 
through erosion (previous to the deposition of the Coal 
Measures). The whole Lower Carboniferous belt rapidly 
narrowed from a width of 75 miles on the north and on the 
south to less than a dozen miles, and at some points was re- 
duced to a mere thread, with only a limited vertical exposure 
m the low bluffs of some stream. In the extreme southwest 
parts of Missouri and in Indian territory and Arkansas the 
Burlington and higher formations again assumed their full 
development and features almost identical with those shown in 
