I20 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 127 
This list includes Black River-Trenton species and some Chazyan species. 
This formation is correlated with the Lenoir of the Southern Appalachians and 
shares a number of species, aside from brachiopods, with it. 
Tulip Creek formation.—This formation is best known in the western part 
of the mountains and the Criner Hills. It consists chiefly of sandstone and shale 
with minor amounts of limestone. The thickness varies between 190 and 380 
feet. Not many brachiopods have been found in the formation. Decker reports: 
Dalmanella sp., Dinorthis deflecta, and Pionodema sp. Neither the first nor the 
last genus has yet been seen in the Simpson group. The middle species is obvi- 
ously misidentified because that species is restricted to the Platteville formation 
which is considerably younger than the Tulip Creek. The following brachiopods 
were taken from this formation: 
Atelelasma sulcatum Cooper Orthambonites minus Cooper 
Hesperorthis matutina Cooper Plectorthis punctata Cooper 
Mimella sp. 2 Valcourea deckeri Cooper 
Murinella sp. 2 V. tennis Cooper 
Correlation of Tulip Creek formation—Abundance and kind of Valcourea 
suggest possible correlation with the Elway formation of Virginia and Tennessee. 
Bromide formation.—This is the uppermost and most widespread of the 
Simpson formations. As at present constituted, it consists of sandstone, shale, 
and limestone, the latter predominating at least in the upper part. The forma- 
tion is thickest at the west end of the Arbuckle Mountains where it measures 
674 feet. The Bromide is divisible into two members: A lower shaly member 
here called the Mountain Lake member of the Bromide formation, and a limy 
member here called the Pooleville member. 
Mountain Lake member of Bromide formation.—This name is suggested for 
the fine sequence of lower Bromide nearly completely exposed along Spring 
Creek on both sides of the line between secs. 8 and 17, T. 2 S., R. 1 W., Murray 
County. The name is taken from Mountain Lake, E34 sec. 22, T. 2, S., R. 1 W., 
near Woodford, Okla., where the shores of the lake exhibit this shale. The lower 
194 feet above the basal sandstone of the Bromide consists chiefly of shales with 
some thin limestone beds. Between 25 and 46 feet above the saudstone the 
brachiopod Sowerbyites is abundant in association with numerous massive bryo- 
zoans. Above this zone Valcourea transversa is abundant. At the top of the 
sequence and just under the light-colored nodular limestones of the Pooleville 
member numerous brachiopods are associated with the cystids Platycystites and 
Cheirocrinus. The uppermost beds contain the brachiopod Multicostella convexa 
Cooper. This brachiopod zone affords a means of comparison with other sections 
and gives a clue to the facies changes. 
To the east, this member appears to become more limy and in places has de- 
veloped bryozoan bioherms and calcarenite banks. Along Oklahoma Highway 
99, about 3 miles south of Fittstown, a fine sequence contains the Valcourea 
transversa zone. Here it occurs just above a thick calcarenite or lime sand. In 
the section 1.8 miles south of Sulphur, along Oklahoma Highway 18, the Sower- 
