The Missoiirian Series of the Carboniferous. — Keyes. 303 
series, shales predominate and the Hthological contrast to the 
Missourian is very marked. Even in deep drill-holes put down 
through Missourian strata the change at this level is readily 
noted. 
The topographic features presented by the Bethany lime- 
stone sharply indicate the passage from one series to the other. 
A noteable eastward facing escarpment everywhere limits the 
western surface boundary of the Des Moines belt. This ridge 
is so prominent a feature of relief that it is disclosed in all the 
profiles of the railroads crossmg it. In the northern part of 
its course the heavy drift deposits are unable to hide it. Further 
southward beyond the limits of glaciation a remarkable belt of 
rugged country is produced. 
The basal member is highly fossiliferous. From below the 
change in faunal features is striking, and attracts at once the 
notice of even the casual observer. 
Top of the Missouria?i Series. The Cottonwood limestone 
has been taken as the crowning number of the Missourian. The 
closing episode in the deposition of the strictly marine beds of 
the region should be regarded somewhat lower down. The 
change need not be made here. The formation is a bufT, mas- 
sive limestone, composed largely of shells of Fusulina. Its 
geographic range is wide, extending from Nebraska, through 
central Kansas, into Oklahoma. Forming a well-marked hori- 
zon it is of great practical use in locating the limits of the 
series. All the watercourses crossing the belt disclose the Cot- 
tonwood rock in vertical cliffs. Being a good building stone 
the course of the limestone at the surface is marked by a long 
line of quarries. 
St.\ges of the Missourian Series. 
General Vertical Sections. Ileretoforv^ it has been impossibk- 
to get a connected section of the Missourian beds. Practically 
no attempt has been made to differentiate all of the formations 
that go to make up the series, though various names have been 
given to certain exposures. The nomenclature of these is fol- 
lowed as far as possible. As represented along the Missouri 
river eleven well marked subdivisions have been recently made 
<out. With their respective thicknesses, they are as follows: 
