a2 University of Kansas Geological Survey. 
Along the western part of its course the stream is held in place 
by the relatively firm Benton limestones and shales from Coolidge 
to near Garden City, so that the migration of the stream northward 
down the gentle inclination of the bedding plains of the Benton 
is an exceedingly slow process, and therefore not very prominent. 
Likewise the unusually strong cementation of the “mortar beds” 
in Finney, Gray, and Ford counties on the north side of the river 
have served as a check to the northern migration of the stream in 
this part of the country. What has likewise helped in this matter 
is a relatively high ridge of the Benton extending westward from 
Jetmore up the Buckner and the Sawlog, so that we have a ridge 
of Benton limestone which strongly resists decay, which has prob- 
ably served to assist in preventing the river from migrating north- 
ward in Gray and Ford counties. But when the eastern limit of 
Ford county is reached no further obstruction was placed to the 
northward migration of the river. The upper channel being held in 
place from Coolidge to Dodge City, and the lower channel being 
held in place in the vicinity of Arkansas City and Winfield, and no 
restraints being placed upon the river throughout the interval it 
would follow in the process of its corrasive actions the path of least 
resistance, and would therefore migrate northward with the gentle 
inclination of the bedding plains of the Dakota sandstone. This 
northward migration probably continued until the condition of base 
level was reached and the filling in processes began, after which the 
stream was unable to corrade the Dakota blufis from Larned to be- 
vond Great Bend, and consequently its northward migration has 
ceased. 
Pawnee Creek. 
The Pawnee is a small stream draining the country north and 
northeast of Dodge City, and south of the Walnut. It enters the 
Arkansas river at Larned. It has an unusually large number of 
tributaries which cover an area of fifty or sixty townships to the 
north of Dodge City. Its upper branches rise in the Tertiary, but 
they soon cut their channels through the Tertiary to the Benton 
limestones and shales. In this way they drain the Tertiary ground 
water and are supplied with running water almost the entire year. 
