On the Triassic Rocks of Kansas and Nebraska. 36 
As we ascend in this group of strata, which comprises, nearly or 
quite all the lower Permian, and much of the upper coal meas- 
ures of Prof. Swallow’s and Mr. Hawn’s section* we find the 
Carboniferous forms very gradually diminishing in numbers to 
be replaced by Permian types, or others rather intermediate in 
their affinities, between those of the Permian and Carboniferous 
conformability, or meeting with any abrupt change, either in the 
as filling the hiatus between the Permian and — coal meas- 
pper Permian 
of their section really represents the Permian rocks, as devel- 
braska and northeastern Kansas, from the coal measures to the 
water level, ate to the northwest. Consequently the elevating 
orces that s uced this inclination of these various formations, 
must have been called into play—as in the region of the Black 
_dills,—after the close of the Cretaceous epoch, and previous to 
_ the deposition of the Miocene Tertiary formations of the north- 
___ * Transactions St. Louis Acad. Sci, vol. i, p. 171. 
| + We found the genus Monotis i deers several hundred feet below the 
___ base of what we understand to be the lower Permian in Prof, Swallow’s and Mr. 
Hawn's section. 
