PROSSER. | The Upper Permian. 57 
western part of Dickinson county to about the middle of the Dick- 
inson-Marion county line, when it turns southwest with a some- 
what irregular line crossing the northwestern part of Marion county 
and southeastern part of McPherson county. 
MAP OF PROSSER AND BEEDE. 
It was planned to accurately trace the line of separation between 
the Permian and Cretaceous systems over all the area under con- 
sideration; but it became necessary to bring the field work to a 
close before this had been accomplished. However, the work as 
far as it was finished showed conclusively that the broad 
valley of the Smoky Hill river in the central part of Saline county 
is underlain by the Permian which extends even farther up the 
river valley than represented to do by Hay; that the upper part of 
the divide in the eastern part of Saline county between the Smoky 
Hill river and Gypsum creek is composed of Cretaceous rocks; and 
finally that on the high divide between the headwaters of the Cotton- 
wood and the southern branches of the Smoky Hill and northern 
branches of the Arkansas, the Dakota does not enter the southern 
part of Dickinson county, but only extends about six miles into 
Marion county to a point about two miles southwest of Durham 
village in Durham Park township. 
Over a part of Saline county at or near the base of the Cretaceous, 
as represented in that county, is an iron-brown sandstone that con- 
tains, in places, abundant fossils. This zone has recently been 
named “the Mentor beds” by Professor Cragin and referred to the 
Comanche series! The nonfossiliferous bluish-gray, greenish, and 
reddish shales overlying the fossiliferous Marion formation of the 
Permian, which are well represented west of the Smoky Hill river 
in the central part of Saline county, have been mapped in the Per- 
mian. For these shales, which may be regarded as constituting a 
formation, Professor Cragin has proposed the name Wellington 
shales? and mentioned their occurrence in Saline county ‘along ‘‘the 
foot of the bluffs of Spring creek from Salina to a point in the south- 
west vicinity of Bavaria.’ 
1F. W. Cragin, American Geologist, Vol. XVI, Sept. 1895, 162-166. 
2 Ee. W. Cragin, Colorado College Studies, Vol. VI, pp. 3, 16-18. 
8 IoxKol. 70%, IM 
