Ulrich—Paleozoic Systems in Wisconsin, 
75 
wMch lie later described as Cryptozoon minnesotense and which 
occur only in the Shakopee. 
On page 34 of the 4th Annual Report the railroad cut section at 
Clear G-rit is described as showing 16 feet of sandstone at the top 
which is called Jordan^ and beneath this 30 feet of dolomitic lime¬ 
stone called St. Lawrence. In the first place the sandstone is not 
the Jordan but may be the New Richmond. It is a red sandstone 
which^ as proved by experience, is of itself sufficient evidence to 
establish its age as post-Jordan, the latter being everywhere a 
grayish white though often iron-stained, case-hardened, interiorly 
friable sandstone, the weathered surface of which commonly is 
studded with highly characteristic rounded, often botryoidal con¬ 
cretions. Otherwise the true Jordan is closely similar to the St. 
Peter sandstone. The dolomite which underlies the red sandstone 
at Clear Grit belongs to the Lower Magnesian and most probably 
is the upper part of the Oneota dolomite. 
At other places noted in the 3rd Annual Report the Jordan is 
properly recognized, but the overlying rock is not the Shakopee 
as then supposed by Winchell but the Oneota. 
Winchell’s discussion of the St. Lawrence, Jordan and Shakopee 
formations in the 5th Annual Report, 1877, is essentially as in his 
4th Annual Report. However, in this year he introduces his sub¬ 
sequently more definitely stated belief that Irving ^s Mendota dolo¬ 
mite and Madison sandstone of south central Wisconsin corre¬ 
spond to the St. Lawrence and Jordan formations of Minnesota. 
That Winchell still correlated the St. Lawrence with what we now 
know to be the whole of the Lower Magnesian,’’ that is in places 
where the locally developed reddish weathering sandstone (the 
New Richmond) is absent, is clearly indicated by his statement on 
page 29, regarding the thickness (250 feet) of the formation at 
La Crosse. 
In 1888 (Final Report, Vol. 2, pp. XXI and XXII) Winchell 
had changed his mind very greatly regarding the relations of the 
early Paleozoic beds in the Minnesota Valley to those exposed to 
the southeast in the bluffs along Root River and to the east along 
the Mississippi. He now recognized that both the Jordan sand¬ 
stone and the St. Lawrence limestone are older than the lower 
main mass of the “Lower Magnesian limestone,” that is than the 
Oneota dolomite as now known, and that the sandstone for which 
