46 A. H. Worthen on the Age of the Leclare Limestone 
the Berberideze and in one or two speics of the Menispermes. 
This occurrence was one of the principal arguments, with which 
the union of these two families in one under the name of Coc: 
culinese was justified. 
t is, as far as I am aware, the first instance that this interest- 
ing body has been found in a plant, which belongs to the Ra- 
nunculacee. This circumstance is, therefore, a proof, that even 
true alkaloids may occur in several plants which belong to dij- 
Jerent families. 
Chicago, Illinois, October, 1861. 
Art. VI.—Remarks on the Age of the so-called “ Leclare Lime- 
stone” and “ Onondaga Salt-Group” of the Iowa Report; by 
A. H. WorTHEN. 
In the very able report on the Geology of Iowa, Prof. Hall 
yas op the limestones at Leclare from the Niagara group with 
which they might seem to be connected, and, mainly on litho- 
logical grounds, assigns them to higher positions as additional 
members of the Upper Silurian series; expressing the opinion 
at the same time, that they are the stratigraphical equivalents of 
the limestones of Gault in Canada, and of the Onondaga Salt 
Group of the New York Series. 
We desire at this time to offer some reasons which seem to us 
. 
shore of the Mississippi in the Autumn of 1858, in the prosecu- 
at Port Byron and Leclare, and from the hurried examination 
we were enabled to give them while upon the ground, we were 
led to seriously doubt the correctness of Prof. Hall’s conclusions 
in relation to the age and true position of these beds. 
subsequent loss of the entire collection made at that time, by the 
burning of the freight depot at Springfield where they were 
stored, prevented any comparison of these fossils with those 
from other localities of Niagara age, and thus arriving at a satis- 
factory determination of the true position to which these lime- 
stones should be assigned. 3 
Subsequently, on visiting the quarries at Bridge ort near Chi- 
cago, we were strongly jonas with the mar! oH resemblance 
which the rocks presented Pa skad ero Ra those at Leclare and 
: fellac cine Hee 
Port Byron. At both local appears as a concretion- 
ary or amorphous mass of limestones, somewhat brecciated, with- 
ee oe 
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