Iron Jyutte^ Montana. — Calvin. '.<o 
plate XLVi, fig. 4, in his "Fossil Corals of Michigan." I am in- 
clined to believe that this fossil is what was described by 
Billings as Eridophjllum siinco^'nse and that its excellent 
preservation discloses features not before ascribed to that 
species. This point can be settled if geologists will carefully 
examine their best preserved specimens. 
Meek has described, from the Devonian of Nevada, in vol. 
IV of the "U. S. Geol. Exploring Expedition of the Fortieth 
Parallel," page 29, a specimen to which this is very closely 
related and to which he gives the name Diphypliyllum fasci- 
culum. This has a similarly placed inner wall, separated from 
the outer by a single row of vesicles, and corresponds in its 
growth, size and number of septa. It differs, however, in hav- 
ing the shorter septa thinner than the others, and in having 
them generally terminate at the inner wall. In the specimen 
here described no such difference in the thickness can be 
detected, and the shorter septa never so terminate, but extend 
into the tabular area. There would also seem to be a minor 
difference in the arrangement of the tabula;. 
Geological Lahoratory University of Michiyan, May''17, ^89. 
IRON BUTTE, MONTANA— SOME PRELIMINARY NOTES. 
By S. Calvin. 
Near Glendive, Montana, occur some excellent examples of 
that peculiar topographic sculpturing which is known as "bad 
lands." Bad lands they certainly are from any ordinary 
point of view, and they extend along on the south side of the 
Yellowstone river for a distance of twelve or fourteen miles. 
The width of the area measured at right angles to the direction 
of the river is not very great. Drainage valley.s cutting through 
them nearly at right angles divide the bad lands into more 
or less perfectly defined masses, that, notwithstanding 
their sculptured ridges and pinnacles and V-shaped 
ravines, rise somewhat prominently above the river and the 
secondary valleys. These several masses are known as buttes, 
and each has its specific designation. 
About ten miles up the Yellowstone westward from Glen- 
dive comes Iron Butte, separated from its neiglil)oring l)uttes 
by the valley of Sand creek on the east and Cedar creek on the 
west. Iron Butte is about as high as either of its fantastically 
carved neighbors, but geologically it belongs to a much lower 
