Geological Reports of the State of New York. 233 
| ~ Murchison’s work on the Silurian system had not appeared, and 
the field was new and to a great extent unexplored. After all 
that had been accomplished by Prof. Eaton in his survey of the 
strata along the Great Western Canal, and by others, the explo- 
ration, as connected with general geology, could scarcely be said 
to have been begun. Probably others yet remain to be accom: 
plished. ‘Too many groups may have been formed. While Cryp- 
tolithus tesselatus retains its place with some others in the Llan- 
deilo flags and in the lower part of the Trenton limestone, and 
in that of the Mohawk at Fonda and in other places, that rock of 
| Wales may yet find its equivalent in our series. The greater 
number and variety of our groups may not involve all those de- 
scribed by Murchison, but only the fullest examination should 
be satisfactory. 
Finally. 'The discoveries which have been made by the pale- 
ontologist. These are many, and of great interest. Omitting all 
the organic remains which have been identified with the Euro- 
pean, and the many new genera and species, there are several 
general facts of great value. 
First: The identifying of the sandstone of Blossburg, Penn. 
with the old red sandstone of Europe, a part of the Devonian 
System. The geological positions of the two rocks are very 
nearly or quite the same; and the remains of the fish, Holopty- 
chus nobilissimus, (apd. baton only in the old red sandstone, 
seem to settle the point conclusively. The stumbling block of 
our geology is thus removed. The Blossburg sandstone is the 
upper part of the Devonian system. The Chemung group, as it 
is called in the geological reports, forms the lower part of the 
vonian, and is characterized by the same shells. pp..42 and 43. 
| Second: The carboniferous system in Pennsylvaaia and Ohio, 
contains many species of shells found in the same system i 
Europe. Even “at Engineer Cantonment, Missouri River,” the 
Shells of the carboniferous system are found, as well as at Pitts- 
| burgh and on the Alleghany Mountains. Eleven species are 
| named as common to the carboniferous strata in our country and 
; Europe. p. 43. 
| Third: ‘Well characterized and undoubted oolite, in the state 
of Ohio,” is for the first time announced in this report. p. 44. 
“Two European species of Trigonia, both of which are re- 
Stricted to the oolitic system,” are presented as the proof. It has 
Vol. x~u, No, 2.—Jan.-—March, 1842. 30 
