PROSSER. | The Upper Permian. 83 
correlation than assigning it a position between the Permian and 
Comanche. The northern apex of the Red-Beds is represented on 
the map as in the southern part of Reno county, its eastern line ex- 
tending southerly across Kingman and Sumner counties to the state 
line, then the formation extends westerly across western Sumner, 
KKinginan, Harper, Barber, Comanche and Clark counties into the 
southeastern part of Meade. 
DESCRIPTION. 
The greater part of the rocks belonging to the terrane popularly 
called the Red-Beds, for which it is proposed to adopt Professor 
Cragin’s name of Cimarron series, consists of red sandstones and 
shales some of which when wet are of a bright red or almost ver- 
milion color. The sandstones are soft and friable, while the shales 
are arenaceous or argillaceous. Thin layess of grayish to greenish- 
gray sandstone and grayish spots are not of infrequent occurrence. 
Near the middle of the terrane the shales contain considerable de- 
posits of salt. This part of the series has been quite fully described 
by) Professor Cragin who considers that the saline crust of the Salt 
Plain of the Cimarron river in northern Oklahoma is derived from 
these shales. The rock salt penetrated by the Pratt salt well is 
also apparently correctly referred to this portion of the Red-Beds. 
Above these salt shales are some red sandstones after which shales 
of variegated color predominate for 100 feet or more in which are 
thin layers of satin spar, selenite and other forms of gypsum. Cap- 
ping these shales is the main mass of gypsum, which is so conspicu- 
ously shown on top of the Gypsum Hills to the southwest of Medicine 
Lodge and which may be readily followed along the bluffs, to the 
west of the Medicine Lodge river, into the southeastern corner of 
Kiowa county; or again, from the Gypsum Hills into the southeastern 
part of Comanche county. The Medicine Lodge gypsum is cor- 
related by Professor Cragin with the similar massive deposits occur- 
ring in the central and southern parts of Oklahoma for he said “the 
principal stratum of gypsum described and illustrated in their Red 
River Report by Captain Marcy and Dr. Shumard as occurring on 
the Canadian and on the forks of the Red river, can scarcely be other 
