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to the east. Upward, these strata are overlain without apparent break
by Pennsylvanian (or Permian) chert beds.

The best section of the "Mississippian" beds is exposed in
the valley of a small creek entering Tetsa River near mile 913. ‘Starting
at the bottom of the creek, the section consists of shaly, limy sandstone
succeeded upward by fine, argillaceous, limy sandstone containing
Productus. These beds effervesce freely with cold hydrochloric acid,
but weather into sandy surfaces. Similar beds, alternating with black
shale, continue stratigraphically upward for 125 feet from the base of
the section, to black chert of the succeeding formation. Near the. top
are numerous spiriferoids. ;

In the base of the section the following fossils were found:
Productus crawfordsvillensis Weller(?):and-Spirifer floydensis Weller.
Near the top of the section: Productus inflatus McChesney(?), Productus
burlingtonensis Hall, P. crawfordsvillensis Weller(?), P. magnus Meek and
Worthen, P. jaSperensis Warren, and Spirifer floydensis Weller. At the
top of the section and just below the chert beds the following were found:
Spirifer floydensis Weller(?) and Syringothyris subcuspidata (Hall)(?).

One-half mile east, near mile 91; highly crinoidal limestone
and hard sandstone stand vertically. The limestone contains the following
fossils: numerous crinoid.columnals, sm1ll for the most part, but some
% inch in diameter; bryozoa, not identified; Productus burlingtonensis
Hall, P. crawfordvillensis Weller, P. magnus Meek and Worthen(?), Ps
inflatus MWeChesney, Chonetes chesterensis Weller(?), Dielasma spe, and
Buomphalus utahensis Hall(?7). | TOR ae

To the west, at mile 92, fossiliferous limestone and overlying
limy sandstone contain & wealth of fossil brachiopods and pelecypods and
some trilobites. A loose block of grey limestone is packed full of
fossils and the adjoining limy sandstones are replete with the same
fauna. The limestone block contains Spirifer close to S. rutherfordi
Warren, Martiniopsis sp. (superficially resembling Brachythyris
suborbicularis (Hall)), Deltopecten sp., and Phillipsia sp. The adjoining
hillside is composed of about 100 feet of dark grey, limy sandstone,
which loses its lime cement through weathering and appears as & brown,
fine-grained sandstone. It contains Spirifer cf. rutherfordi Warren,

Me Teint Opsae Spe, Deltopecten sp., and Euconispira taggarti (Meck).

There are probably about 200 feet of these beds exposed westward
along the hillside, where they rise in a small anticline and are overlain
by chert beds of the succeeding formation.

Six hundred and fifty feet up the hillside above mile 94
Dielasma sp. occurs in brown calcareous sandstone. This probably represents
some beds of the "Mississippian" series.

There are two distinct faunas in these "Mississippian" strata,
the lower one characterized by various productids and the upper one by
spiriferoids. Neither of these faunas has much in common with faunas so
far described from the Banff, Moose Mountain, Jasper, Peace River, or
Liard River sections. Warren has listed Productus jasperensis, Pe
burlingtonensis, Dielasma chouteauensis, and two species of Brachythyris

(but not suborbicularis) from the Banff shale at Jasper.

In comparison with the Illinois section, it is clear that both
_ faunas are dominaytly Osage (Burlington ond Keokuk). Chester affinities
are suggested by Chonetes chesterensis and Productus inflatuse