226 EEPORT OF THE AMERICAN COMMITTEE. 
Survey, 1841, T. A. Conrad gave a classification of the New 
York rocks, in which the formations above the Onondaga lime- 
stones and below the " Old red sandstone " are considered as 
equivalent to the upper Silurian of Murchison (see 1. c. pp. 31 
and 43), referring to the " Old red sandstone " or " Devonian " 
only the "Chemung" and '^Catskill groups" of our modern 
classification. In the final report (1842, for the 3d district, p. 
13), Lardner Vanuxem proposed the name " Erie Division " (of 
the New York system) for the series of deposits called upper 
Silurian by Conrad, but added to them the Chemung group. 
His " Erie Division " included the " Marcellus shales, Hamilton 
group, Tully limestone, Genesee slate, Portage group, Ithaca 
group, Chemung group." (See 1. c. p. 13.) On page 171 of 
this report, Mr. Vanuxem states that the last three groups, i.e., 
the Portage, Ithaca and Chemung groups, "appear to correspond 
with the Devonian system of Phillips." In the final report for 
the 4th district, 1843, Professor James Hall adopted the same 
classification, but expressed the opinion that the Devonian system 
of Phillips should include also "a portion of the Hamilton." 
(See 1. c. p. 20.) To appreciate this point, it must be remembered 
that at that time, 1843, the Hamilton group was regarded as the 
upper measure of the Silurian. In 1846 (Paleontology of New 
York, vol. 1, p. xvii), Professor Hall first announced the opinion 
that " from a paleontological point of view tlie deposits down to 
the Oriskany should be included in the Devonian." Thus the 
term Devonian became established in the nomenclature of 
American Geology. 
Although the precise boundaries, both above and below, have 
suffered some modifications with increasing knowledge, the 
Devonian system of Sedgwick and Murchison was shown to be 
unmistakably present in American rocks by the identity or close 
relationship of the fossil species found therein. 
The name " Erian " was proposed by Sir William Dawson in 
1871, as an equivalent for Devonian as used in America. (Re- 
port of the Geological Survey of Canada : On the Fossil Plants 
of the Devonian and Upper Silurian of Canada, by J. W. 
Dawson, 1871, part 1, p. 10.) The name is proposed "for the 
great system of formations intervening between the upper Silu- 
rian and the lower Carboniferous in America." The term 
" Erian " was an adaptation of " Erie Division " early adopted 
