. Emmons on American Geolocy. 403 
__ berg series, and it is upon the upturned edges of these different 
‘Strata, that the liassic sandstones of the Connecticut and Hudson 
_ Valleys (which our author calls triassic and permian,) repose ina 
nearly horizontal altitude, and are penetrated by outbursts of trap, 
having not even the most remote connection with the great 
northern anticlinal, which is of the palwozoic age. Montreal lies 
entirely out of the line, being some thirty miles to the northwest 
of this anticlinal, and in the midst of a broad area of almost hori- 
. zontal rocks of the Champlain division, broken here and there by 
\ masses of trap, which with beds of volcanic aslf, are interstratified 
with different members of the Champlain group. Yet we are told 
by Mr. Emmons, that “the phenomena justify us in regarding 
Montreal as the centre of a highly disturbed district.” _ , 
The object of all this is to pave the way for his Taconic sys- 
tem, upon which, although it may be superfluous to most of 
our readers, we shall make a few remarks. The T'aconic rocks, 
graphical structure of the region; for while the Taconie rocks 
; are supposed to play a very important part on the east side 
Helderberg series, and north of the parallel of 45°, although 
much altered, they exhibit their characteristic fossils. The Lower 
se crystalline strata be, as Mr. Emmons maintains, older even 
than the Taconic rocks, we are required by his theory to admit that 
both the Taconic and Lower Silurian strata are every where want- 
mg along the southeastern side of these mountains. ‘The simple 
Solution of these difficulties, as long since shown by the Geological 
Survey of Canada, is this: the Green Mountains are the upper 
Portions of the Champlain division in an altered condition, and 
