LOWER PALEOZOIC. 209 
honor to read before the Committee at the Albany meeting, and 
in accordance with the suggestions of Prof. James Hall, Prof, 
Jules Marcou, Prof. C. H. Hitchcock, and Prof. A. Winchell, 
the term Taconic is made coordinate with the term Cambrian, 
and they are both applied to well-known faunas, and also to the 
rocks containing those faunas, in accordance with the design of 
the authors of those terms. 
The scheme of Professor Newberry, while recommending the 
term Taconic for a prominent part of the primordial fiinna, 
diverges from that of Mr. Walcott in not including the Potsdam 
[i. e., the St. Croix beds of the following table] in the primordial 
zone. He, on the other hand, places this sub-fauna, which 
certainly has a primordial facies, in the Lower Ordovician, which 
is not in accordance with the idea of the author of the terra 
Ordovician, although it furnishes a coarsely fragmental base for 
the bottom of the Silurian as he has limited it. 
For reasons which the writer has given recently elsewhere,* he 
is also constrained to recommend, in consonance with the opinions 
of Professors Hitchcock, James Hall, A. Winchell, Jules Marcou, 
and Dewalque, of the general committee on nomenclature of the 
last international congress, and in harmony with the fundamental 
idea of Mr. Sedgwick, the author of the term, that the term 
Cambrian be applied to the rocks of the second fauna. 
In making the recommendation that the term St. Croix be used 
as a sub-faunal designation, as about equivalent to Mr. Walcott's 
use of the faunal designation Potsdam, it may be well to give the 
reasons that have actuated your reporter. They are briefly as 
follows : 
1. The fossils embraced in this sub-fauna were described first 
from the St. Croix formation of the Northwest, and with slight 
exceptions, so far as they have been found in eastern New York, 
they are in beds that lie above the typical original Potsdam sand- 
stone, and are embraced in what has been known as the Calciferous 
sandrock. 
2. It is true that Professor Hall and also Dr. D. D. Owen at 
first placed these fossils conditionally in the horizon of the New 
York Potsdam sandstone, although no fauna at all comparable to 
them had then been found in that sandstone. Their authority 
was followed by nearly all geologists, and the sandstones of the 
* American Geologist, March, 1888. 
