168 University of Kansas Geological Survey. 
shales, though this position is hardly tenable on account of the in- 
creased thickness at each end. By other observers it has been con- 
sidered as evidence of unconformability due to erosion preceding 
the deposition of the Comanche series. Between the red shales and 
the base of the black Kiowa shales is a brownish stratum consisting 
of either shales or sandstone. This occupies the position of the 
Cheyenne sandstone and also agrees in character with the Big 
Basin sandstone of Cragin. The unconformability below seems to 
unite this sandstone with the Kiowa rather than with the Red-Beds. 
Atong the slopes of the bluffs on the opposite side of the creek are 
also excellent exposures of black argillaceous shales forming the 
lower part of the Kiowa. From these black shales as well as from 
those on the opposite side, remains of vertebrates were collected 
and described by Doctor Williston. Prefacing his description of the 
forms is a brief description of the geology of this region, in part as 
follows: “Suffice it to say here that in the region which we exam- 
ined—upper Bluff Creek and Sand Creek with its tributaries—I 
found the beds in which the vertebrates occur, Cragin’s No. 4, lying 
unconformably on the rocks of the Trias and surmounted by a thin 
stratum of the characteristic Dakota sandstone, and the thicker 
Pertiary sandstones of the uplands. The material is a dark blue 
shale, so strongly impregnated with iron that the fossils are always 
more or less injured after exposure. On moderately inclined slopes 
the bones, where found at all, were always disintegrated and in- 
crusted with sulphate of lime. For this reason, they can be sue- 
cessfully sought only on steep slopes, and such are infrequent. 
Furthermore, the bones have always been found isolated, never 
together, so that it is hardly to be expected that even a tolerably 
complete knowledge of the fauna will be obtained in many years. 
The bones are found throughout the whole thickness of the shale, for 
fifty or seventy five feet. The remains, meagre as they are, are of 
great interest, because they represent the oldest marine cretaceous 
fauna of America thus far discovered.’ i 
From the above locality the Kiowa shales follow the line of the 
bluffs west of Little Sandy creek, five miles to the south, where the 
1S. W. Williston, Kansas University Quarterly, Vol. III, July 1894, pp. 1, 2, Law- 
rence. 
