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of North America with those of Europe. 179 
rts, as a matter of concession, and it is to be regretted that such 
an artificial classification was ever, for a moment adopted, although 
only with a wish of giving unity to the several reports. All ar- 
rangements of this kind, indicating geographical limits or loca- 
tions, are of very trifling importance when compared with those 
founded on Paleozoic characters. In the present instance, the 
first division embraces all the lower strata to a very natural hori- 
zon, while the second includes only a part of a natural group, the 
upper portion of which is carried into the third division. The 
third division includes a portion of two natural groups, but em- 
bracing neither of them entirely. It is to be regretted that these 
divisions are perpetuated in any publication, since at the time of 
their adoption, they were assumed merely as geographical subdi- 
visions, and regarded as of no more value than to indicate the re- 
gion or neighborhood, in which certain rocks or groups occupied 
the surface and surrounding country. 
M. de Verneuil proposes a union of several of the smaller 
groups ; in which we agree with him, having already adopted 
them in the paleontological arrangement. Notwithstanding this, 
we are still disposed to retain all the names given, rather than to 
merge any of them in more general terms; except for the expres- 
Sion of a series which shall unite several minor beds, all of which 
elsewhere. It is easy to designate great groups, but that such 
groups shall be permanent, it requires that their elementary parts 
shall have been studied with care. It is much easier to unite the 
formations, our author continues his descriptions of the series in 
the stratigraphical order. Regarding the calciferous sandstone as 
a distinct mass, he follows with some reason also the arrangement 
adopted in the New York reports, of uniting the Chazy, Birdseye 
and Black River limestones in one group; though each possesses 
peculiar fossils, and, where fully developed, are in fact very slightly 
connected by their organic remains. Still in western localities 
there appears to be less positive means of separating them.* 
* These rocks contain together about ei ty species. Of these only two or three 
known in the Chazy, are found in a higher position, and a single species of the 
Srconp Series, Vol. V, No. 14.—March, 1848. 24 
