IOWA ACADEMY OF SCIENCE 
239 
situations in which such faulting is entirely out of the question.* 
It should be noted that faulting and slipping is not so universal as 
might appear from his statement. In many localities with gentler 
slopes and flatter areas where fossiliferous loess occurs, there is 
no evidence of such slipping and faulting in fresh cuts. In such 
localities it is only the faces of road and older railway cuts that 
present this phenomenon, and that on a small scale. Yet in the 
newest cuts, which present no evidence of slipping, continuous 
fossiliferous deposits, approximately horizontal or following the 
rather flat contours, may often be traced for considerable distances. 
The writer has observed such continuous deposits in fresh cuts in 
the Gaulocher brickyard at Iowa City, in the first cut west of Iowa 
City on the electric line, in the Danner cut near Coralville, and at 
other points northward on the same line, along the Chicago Great 
Western railroad just southwest of Carroll, along the Mississippi 
Central railroad near the foot of Union street in Natchez, Missis- 
sippi, and in other street, road and railway cuts, both fresh and 
old, in various parts of the Mississippi valley. 
In all these cases the slopes were so gradual that absolutely no 
evidence of step-faulting appeared, as evidently none had occurred. 
Yet the fossils were scattered in practically horizontal continuity, 
in some cases through several hundred feet of these deposits, and 
to a depth of from one to more than twenty feet. It is impossible 
to conceive of a method of cracking and slipping by which it would 
be possible to introduce these shells after the formation of the 
deposit, and give to them their present horizontal distribution. 
It would be especially interesting to hear Professor Todd's appli- 
cation of his explanation to cases like that at Carroll, where a 
fossiliferous loess underlies a distinct non-fossiliferous loess, or 
that at Muscatine where a fossiliferous loess lies under the Illinoian 
drift. In the first case the first long cut along the Chicago Great 
Western R. R. southwest of Carroll, Iowa (See Plate I, fig. 1), ex- 
poses several feet of Kansan drift over which lies a bed of bluish- 
gray loess varying from two to four feet in thickness. This loess is 
very fossiliferous, and the fossils are scattered throughout its length, 
but above it a layer of distinctly different yellow loess, several feet 
in thickness, show T s no trace of shells. An exposure facing Hershey 
Ave., near Green street in Muscatine, Iowa, shows about three 
feet of bluish-gray fossiliferous loess resting upon Kansan drift, 
and covered by several feet of Illinoian drift. It appears as a light 
* Some of these localities were mentioned in the discussion in 1897, and must have es 
caped Professor Todd’s memory. 
