700 THE JOURNAL OF GEOLOGY. 
The amount of flint contained in the rock varies. In some 
localities it is scarcely perceptible while in others the quantity is 
sufficient to make the rock comparatively valueless for economic 
purposes. There are very few fossils, with the exception of 
Fusulina cylindrica, Fischer, which is extremely abundant in the 
upper part of the stratum. The quarrymen call these fossils 
grains of wild rice, and on account of their great abundance Pro- 
fessor Swallow called the stratum the ‘“‘ Fusulina limestone.” * This 
limestone forms one of the most important features in the strati- 
graphy of the Upper Paleozoic rocks of Kansas and in many res- 
pects is as valuable for stratigraphic purposes as the Tully or 
Corniferous limestones in the Devonian of New York. 
Fauna of the Cottonwood shales.—The yellowish overlying 
shales, which may be called the Cottonwood shales, constitute 
one of the most fossiliferous horizons of the Carboniferous, 
although there are but a few species that are extremely abundant. 
The immense number of fossils in this shale was noted by Pro- 
fessor Haworth and Mr. Kirk, who stated that in the shale of the 
Rettiger quarries ‘‘ marine invertebrate fossils are unusually abun- 
dant,’’? but in general this, its most striking characteristic wher- 
ever exposed, seems to have been overlooked .3 
Wherever the shale has been exposed for some time to the 
action of the atmosphere large numbers of loose fossils perfectly 
Magnesian carbonate - . = hey ls “3 
Sulphates - - - - OO ™ 
99-50 © 
Mineral Res., U. S. for 1893, p. 563. The samples came from the Rettiger Bros.’ 
quarry, the crushing strength being 6800 lbs.; weight per cubic foot 161.6 lbs.; and the 
specific gravity 2.59. 
t Prel. Rep. Geol. Surv. Kans., p. 16. 
2 Kans. Univ. Quart., Vol. II., p. 113. 
3Professor Broadhead probably noticed the fossils of this shale, but his reference 
is quite indefinite. The Professor mentions quarries in the Cottonwood Valley con- 
taining ‘‘about six feet of very good building stone,” probably the Cottonwood lime- 
stone, and says, “the associated shale beds abound in fine fossils, including Prod. 
semireticulatus,; Hemp. crenistria; a large variety of Chonetes granulifera and Athyris 
subtilita, Archeocidaris, and a Crinoid” (Trans. St. Louis Acad. Sci., Vol. IV., Pt. IIL., 
p- 492). 
