54 THE PALEONTOLOGY OF MINNESOTA. 
{Other Cretaceous. 
In 1887, Mr. H. V. Winchell discovered Cretaceous shales and lignites on the Little Fork, and on 
the Bowstring (or Big Fork) river,* but besides the foraminifers already described by Messrs. Woodward 
and Thomas, no fossil was identified specifically. Mr. Winchell mentions ‘‘cycloid fish scales and other 
fossiliferous remains.” 
As to the eastward extension of the Cretaceous sea in Minnesota, there is much reason to suppose 
that it covered the whole state. In the first annual report of the Minnesota survey+ attention was 
called to certain lignites and green clays and shales which exist in the Grand Traverse region in the Lower 
Peninsula of Michigan, which Mr. A. D. White, of the Michigan survey of 1860, did not regard as belong- 
ing to the drift deposits with which they had usually been classed. In 1872, soon after the writer entered 
upon the Minnesota survey, information was sent to him by Prof. Frank H. Bradley, of a memorandum by 
Mr. Thomas Daniels, C. E., made in 1865, purporting to describe a “half-mile outcrop of ‘ Kocene’ fossil- 
iferous beds on the Nemacogin river in Wisconsin, about half way from St. Paul to Superior city, and per- 
haps thirty miles east of a straight line connecting those places.” This memorandum was sent, at his 
request, to the late Prof. R. D. Irving; but, aside from a brief reference to it in the American Journal of 
Science} there has been no published note of Cretaceous at that point in Wisconsin. In reviewing the 
clays of the state of Minnesota for brick-making, in 1880,4 an alliance was shown to exist between the 
alkaline blue clays, referable to the Cretaceous ingredient in them, making on burning, a cream-colored 
brick, and the blue drift-clays of the vicinity of Milwaukee which also make cream-colored brick; and this 
alliance was thought to point to the former existence of a Cretaceous area in the region north from Milwau- 
kee whence the same Cretaceous ingredient could have been supplied to the Milwaukee drift clays. At 
Chicago, Dr. Edmund Andrews has shown that the water derived from the till, on analysis, contains a 
greater ‘“‘saline” ingredient than water from recent clays or from the surface. There is no Devonian or 
Silurian shale or clay that is known to be so charged with alkaline elements as the Cretaceous beds of the 
west to which this effect can be attributed. Quite recently Mr. B. W. Thomas has found, as stated by 
Messrs. Woodward and Thomas in this volume (page 28), the same species of Foraminifera, in limited num- 
bers, in the boulder-clay at Chicago, as are distributed in the boulder-clays throughout Minnesota, and 
which are referable directly to the Cretaceous. Lastly. in studying the iron ores of the state of Minne- 
sota, in 1889 and 1890, certain analogies were noticed|| between the Cretaceous iron ores of Minnesota and 
certain limonitic ores of Wisconsin, allying them all together, and pointing to a common origin, thus 
extending the waters of the Cretaceous ocean over a large area in central Wisconsin. 
Notwithstanding all these indications (which are given for what they may be worth) there is not 
yet any known locality, between Minnesota and the Grand Traverse region of Michigan, where any actual 
outcrop of such strata is known. 
*Sixteenth Annual Report, pp. 403, 481, 434, 
+Op. cit. pp. 110-11, 1872, 
#Op. cit. vol. x, [8], 307. 
§Preliminary report on the Building stones. etc.. of Minnesota, 1880, in the Eighth Annual Report. 
The Tron Ores of Minnesota. Bulletin No. vi, 1891, p. 151. 
