The Taconic — Marcou. 17 
identical in the New York system." Agrlc^ N. T.^\o\ :. pp, 
361 and loS. 1846. All that is true to the letter, and is as ad- 
mirable an instance of observation and classification as is the 
paleontological discovery of the primordial fauna in America. 
The adversaries of the Taconic series at first denied it in toto 
dismissing the question, by saying that the Potsdam was the 
oldest stratum lying on the primitive crystalline rocks, and 
that there wei"e no strata below. For the Taconic of Dr. Em- 
mons, it was only the lower Silurian or Champlain division, the 
upper Silurian, the Devonian and even the Carboniferous, each 
and all metamorphosed. For them the Hudson River group was 
most important, with a thickness of twenty thousand feet; and in 
it was the Olenus zone of Scandinavia described by Hisinger 
and Angelin, and the primordial zone of Bohemia of Barrande. 
Such was the creed promulgated by Mr. James Hall, and ac- 
cepted and sustained by Messrs, Logan, Dana, the brothers 
Rogers, Mather, Hitchcock and their followers. 
It was simply the suppression of a whole series, divided 
now into three systems (lower, middle and upper Taconic,) 
of a thickness of at least 35,000 feet, containing three great 
faunas, and the most important which is on earth, being the 
beginning of the animal kingdom (infra-primordial, primordial 
and supra-primordial). 
We have here the two or three first applications of "prin- 
ciples," and certainly all of an extremely easy application for 
disposing of the most difficult and important part of the great 
time divisions of the sedimentary strata of North America. 
Those "principles" are simply; (i) suppression of 25,000 feet of 
strata; (2) identifications of primordial fossils with some of the 
upper part of the second fauna; (3) transposition of the pri- 
mordial genera Olemis and Atops above the second fauna; and 
(4) explanation by metamorphism of all the strata existing in 
the Taconic area, i-eferring them to the Lower and Upper Sil- 
urian, the Devonian, and the Carboniferous. Such are the 
"principles" made use of by adversaries of the Taconic system 
from 1S42 to i860. 
Directly after the publication of the paper entitled: "On 
the primordial fauna and the Taconic system by Joachim Bar- 
rande, with additional notes by Jules Marcou," Boston, 24 Dec. 
