¢ 
T. 8. Hunt on some points in the Geology of Vermont. 229 
Conocephalites Teucer Billings, cited by Mr. Perry as charac- 
_ teristic of these supposed lower slates, is, according to Mr. B., 
common to the slates and to the associated Red Sandrock. 
dd. The black slates to the east of the Potsdam which 
belong to the Levis formation, and afford its characteristic fos- 
sils at various points all along their outcrop. We have seen 
that the Levis formation with its graptolitic slates had been 
at an early date confounded with the Utica and Hudson River 
formations in Canada, and all of these have now been con- 
founded with the Georgia slates to make up the Middle Taconic. 
inally, it remains to be said that this view consigns to a still 
more remote period, the lower Taconic, the great mass of the 
Quebec group which lies between the lines of fault already 
alluded to and the Green mountains, including the white mar- 
bles or Eolian limestones with their associated fossils, the Or- 
thoceratites, Maclureas and other fossils already named, which 
no paleontologist would think of assigning to a horizon below 
the Potsdam. 
0 sum up in a few words—all the evidence, paleontological 
and stratigraphical, as yet brought forward, affords no proof of 
the existence in Vermont of any strata (a small spur of Lauren- 
. 
tian excepted) lower than the Potsdam formation, which the 
Present advocates of the Taconic system regard as forming its 
summit. The supposed more ancient Middle and Lower Taconic 
‘on Kuver, and in part of the Quebec group, which also consti- 
tutes the Lower Taconic. To the upper portion of the Quebec 
That strata still older than the Potsdam of New York and 
Vermont were deposited in some portions of the oceanic area, 
Foppparent from the existence in New Brunswick of the St. 
_ Yohn’s slates holding a primordial fauna older than the Pots- 
lie 7 and it is not impossible that their equivalents may under-’ 
he the Potsdam formation of Vermont. No such rocks have, 
“Owever, as yet, been detected either in Vermont or Canada, and 
: sheer be 
<< to preserve the name of the Taconic system as the designation 
. ° . 
&series of rocks older than the Potsdam and lying uncon- 
: formabl 3 
_ J tably beneath it, is simply to perpetuate an unfi ate 
_ Tustake which I believe Dr. Emmons, if now living, would, with 
paleontological evidence at present before the world, be the 
firs = P 
acknowledge, ee 
ATSt to 
