398 New Genera of Fossil Corals. ; : 
with each other, is simply a fact which admits of no controversy. 
We have then at least seventeen* independent variable quantities 
which harmonize together in a complicated formula. In regar 
to each of these there are many chances to one against its value 
being such as to produce the existing harmony ; hence the prob- 
ability is almost infinity to unity against the accidental coinci- 
dence of the whole. The conclusion seems irresistible that my 
formula is the expression of a law of nature. 
Pottsville, Pa., March, 1851. 
Arr. XLV.—New Genera of Fossil Corals from the Report by 
James Hatt, on the Paleontology of New York. 
Silurian and Devonian rocks, and in no part of the world is this 
series of strata more fully developed, or more abundant in organi¢ 
remains. The completeness of the system here displayed will 
make it classic ground for the student of the ancient life on our a 
globe, and Mr. Hall’s work, in which these relics of antiquity ie 
are described, must become of standard importance the worl i 
over. ‘The first volume, a thick quarto, with nearly a hundred a 
New Genera of Fossil Corals.—1. Clinton Group. — 
Genus Hetoprora, Hall, p. 44.—[Bryozodid ?} Simple. 
branching cylindrical stems, often swelling at the upper extts 
Rarth py 
i 
iz.: The Wistances and jjingses of Mercury, Venus, the 
