282 Scientific Intelligence. 
them; while the whole Taconic system, according to Emmons, lies beneath 
these formations. (Hitchcock; Geology of Vermont, p. 386. 
But if the Taconic system has been misunderstood by Mr. Barrande, it 
has now been completely travestied by Mr. Marcou. Let us compare the 
system as defined by its author, with the view of it given by Mr. Marcou 
in his late communications to the French Academy, and in the paper now 
before us. 
Ist. Mr. Emmons asserts that the Potsdam and Calciferous repose un- 
Mr. Marcou, on the con- 
_8d. Mr. Emmons, as we have already seen, maintains that the rocks of 
his system owe their apparently inverted succession to a series of disloca- 
tions and upthrows; hence it results that the newer seem successively 1 
pass beneath the older strata, the whole series having a general eastward 
dip, towards the Green mountains. Mr. Marcon, on the contrary, 
that “crystalline and eruptive rocks occupy the centre of the Green moun 
tain chain, and that the Metamorphic and other stratified rocks have beet 
turned over on each side, to the east and the west, presenting the fan- 
structure, and all the accidents which accompany @ com 
simply a fiction of Mr. Marcou’s invention, unsupported by a single 
g 
tourist who spends a week in the-region? We conceive Mr. Emmons © 
have in his explanation of the physical structure of the — 
rocks; but it is at any rate conceivable, and to a certain extent ape 
that the granites of the Alpine summits, 
9 arrangeme bed by De 
of a synclinal and not of an anticlinal structure. Mr. Marcou tead of 
Sing, a8 Was once supposed, eruptive rocks, are now known to be 
