68 THE DEVONIAN AND CARBONIFEROUS. [dull. 80. 



A few copies of the paper doubtless came to America, but the form 

 in which it had most effect upon American geology was the condensed 

 translation and review of it by Mr. James Hall, which appeared in the 

 American Journal of Science. 1 



In the present essay the original paper and HalPs comments upon it 

 will be discussed together. 



Mr. HalPs Review of M. de VerueuiPs Study of the American Pale- 

 ozoic was entitled " On the Parallelism of the Paleozoic Deposits of 

 North America, with those of Europe; followed by a Table of the 

 Species of Fossils common to the two Continents, with indication of 

 the positions in which they occur, and terminated by a critical exami- 

 nation of each of these species ; by Ed. de Verneuil (translated and 

 condensed from Bulletin of the Geol. Soc. of France, 2d ser., vol. 4 for 

 this Journal; by James Hall, New York State Geologist)." 



This review is of great importance historically, as it shows how the 

 classification of the New York strata was perfected by comparisons 

 with the European strata and their fossils. 



M. de Verneuil, one of the ablest paleontologists of the time, had 

 been associated with Murchison in studying the Russian series. This 

 had led to a careful comparison of the English Silurian and higher 

 rocks with those of Russia, and had fitted him preeminently to recog- 

 nize corresponding species, zones, and faunas in the New York and 

 American series. And this " review " of his report on the u parallel- 

 ism " was by the rising paleontologist of New York, who, better than 

 any other American, understood the fossils and the arguments pre- 

 sented. 



De Verneuil appreciated the great value, for classificatory purposes, 

 of the New York j*eries. He said, " No country in Europe offers us so 

 complete and uninterrupted a development of the Silurian and Devo- 

 nian systems," and "this series presents a continuous succession of 

 deposits which are superimposed in regular stratification." 2 



The various strata of this New York system had been defined and 

 named in their stratigraphic order, each different kind of rock receiving 

 a distinct, generally geographic name. These formations had been 

 grouped together arbitrarily on grounds of their geographic outcrops ; 

 as Cham plain, Ontario, Helderberg, and Erie divisions. By some of 

 the State Geologists they were regarded as merely convenient group- 

 ings of the rocks for reference, and of no scientific value. 



In the final reports attempts had been made to correlate them with 

 the English subdivisions, as given by Murchison and others, but these 

 correlations were incorrect, as the result has shown. 



No satisfactory method of classifying the individual formations into 

 more comprehensive groups had been attained. De Verneuil proposed 

 to unite them into groups according to their paleontologic affinities. 



1 Second series, vols. 5 and 7, 1848. * Am. Jour. Sci., 2d ser., vol. 5, p. 178. 



