SO-CALLED CRETACEOUS DEPOSITS IN MINNESOTA 683 
soon corrected through the identification of fossils by H. S. 
Williams. The occurrence of a true Cretaceous fossil in this 
Pleistocene deposit does not prove the origin of the clays, 
because also pre-Cambrian rocks and Devonian fossils are 
scattered quite abundantly in it. The Austin clays are not 
Cretaceous and it is very doubtful that they ever could have been 
such. 
Another supposed Cretaceous deposit has been described, 
also by N. H. Winchell in the northeastern part of Mower 
county. There is, in this district, a ‘white pebbly conglomerate 
which passes into a ferruginous grit.” In the adjacent part of 
Fillmore county, the same occurs, and was identified as Cretaceous. 
Near Spring Valley, a few miles farther south, a blue clay is said 
to represent the Cretaceous. No actual outcrops were known of 
strata zz széu, and one might not now refer any of these to the 
Cretaceous, especially since the ‘“ Austin rock” is now known 
to belong to a different formation. Indeed, they were so referred 
only with doubt by Professor Winchell. Of course, Cretaceous 
as well as Devonian, Ordovician, Cambrian and older rock débris 
might be found commingled in the Pleistocene drift. 
In Goodhue county, about sixty miles northward from Austin 
and ninety east of New Ulm, there is another deposit consisting 
of interstratified clay and sand, which is described byaeNe Et. 
Winchell as Cretaceous.t Fossil leaves have been found in the 
sandstone and are identified by Leo Lesquereaux as Cretaceous 
fossils.7, I have verified the occurrence of the leaf imprints, 
though of course their identification is not questioned. The 
fossils belong to the same age as the strata and the latter are 
therefore of Cretaceous origin since the former are. 
Before describing this patch of sand and clay, it may be 
recalled that the deposit lies beyond the limits of Wisconsin and 
Iowan drift in the region of loess and Kansan or pre-Kansan 
drift. It is in an undulating prairie bordering on the deep 
valleys which lead to the Mississippi valley about twelve miles 
Op. cit., Vol. II, p. 43. 
?They are described in Final Rep., Vol. III, Minn. Geol. Sury. 
