Part I. Report of progress in 1869, by J. S. Newberry, chief geologist. Part II. Report of progress in the second district, by E. B. Andrews, assist. geologist. Part III. Report on geology of Montgomery County, by Edward Orton, assist. geologist.

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larger, more powerful, and more singular in their organization than any
of those immortalized by Hugh Miller. These fishes we owe to the industry and acuteness of Mr. Hertzer, and in recognition of that fact I
have named the most remarkable one Dinichthys Hertzeri, or Hertzer's
terrible fish. This name will not seem ill chosen when I say that the fish
that now bears it had a head three feet long by two feet broad, and that
his under jaws were more than two feet in length and five inches deep.
They are composed of dense bony tissue, and are turned up anteriorly
like sled runners; the extremities of both jaws meeting, to form one
great triangular tooth, which interlocked with two in the upper jaw
seven inches in length and more than three inches wide. It is apparent
from the structure of these jaws that they could easily embrace in their
grasp the body of a man —perhaps of a horse-and as they were doubtless moved by muscles of corresponding power, they could crush such a
body as we would crack an egg-shell.
THE ERIE SHALE.
The mass of shale to which I have referred as forming the Lake shore
is on the eastern border of the State, several hundred feet in thickness,
but, like most of our rocks composed of mechanical sediment, it thins
out toward the west, and in central Ohio has entirely disappeared. This
formation also for many years formed debatable ground to geologists,
but during the past summer we have been able to gather from it numerous fossils (Spirifer Verneuilii, Leiorhynchus mesacostalis, &c.) of species
which prove the beds containing them to be the equivalent of the Chemung group of the New York geologists. The Erie shales are bluish or
greenish in color, but, though in some places four hundred feet thick,
they include less of interest or value than perhaps any other formation
in our series, and therefore need not detain us. They form, as we now
know, the summit of the Devonian formation, and immediately underlie
the most interesting and valuable division of our geology.
THE CARBONIFEROUS SYSTEM.
As is known to most persons, the Carboniferous formation is so named
from the beds of coal it contains in Europe and America, where our geological nomenclature originated. Researches in other countries, made
within a few years past, have, however, proved that more recent groups.of rocks-as the Triassic in China and the Cretaceous and Tertiary in,our western territories-include an equal amount of combustible matter,:and perhaps as well deserve the name Carboniferous.
In Europe the Carboniferous formation is divided into three great
groups; the Lower Carboniferous or Mountain Limestone, the Carboniferous Conglomerate or Millstone Grit, and the Coal Measures, or the