4 
of North America with those of Europe. 177 
cies present themselves in the same order in erica as in 
Europe, or in other words, is there in the succession from the 
most ancient fossiliferous beds to the coal period inclusive, a law 
common to the two continents? 2nd, is it possible to trace, 
necessary to a solution of this double question, Ist, do the spe- 
in Am 
Ttesearches, we are induced to accord to the species common to 
the two continents, has induced us to give the list of them with 
the divisions in which they are found, and to give to this table 
some details upon each of these species, and in particular upon 
their different positions. 
Composition of the Paleozoic strata in the state of New York. 
In the present state of our knowledge, there is perhaps no series 
of formations which is extended in a continuous manner over a 
nown the mineral riches of their soil, and which have given rise 
to very valuable publications ; but the state of New York has done 
More, she has undertaken the noble task of publishing a complete 
work upon her Natural History. The geological labors confided to 
eminent men, have thrown a brilliant light upon the geological 
Structure of this part of the United States. By one o 
ppy chances of which the history of science offers us examples, 
the territory of the state of New York presents us, below the 
carboniferous system, the Paleozoic series most complete. Every 
