Gypstini Deposits. Kcycs loi 
appear to belong" to two taxonomic groups of serial ranks. 
Names have already been given to these terranes, so that at 
best the term Permian seems to be superfluous, and will prob- 
ably have to be dropped altogether as a geological title. 
The fact that the gypsum deposits have not as yet yielded 
fossils does not militate in the least against correlation with 
fossiliferous terranes of other Iowa localities. If the beds 
were to be paralleled with those of the Niobrara, for example, 
we would not expect, necessarily, to find the same fossils in 
both ; we would naturally be somewhat surprised if we did not 
come across species that were not identical. The difference 
in local environment would demand very different faunas in 
the two localities. All evidence as to age or secjuence based 
upon fossils must for the present be excluded, because organic 
remains, while they no doubt exist in the gypsum shales, and 
perhaps abundantly, have not yet been reported. 
In looking about for critical criteria bearing upon the age 
of the Ft. Dodge gypsum deposits we find that the marked 
miconformity at the base of the formation is a feature that is 
stratigraphically of first importance. Its physiographic con- 
nections when established must appear exceptionally trustwor- 
thy as data by which to determine the geological age of the 
deposits immediately overlying. In the region under consid- 
eration there are two great horizons presenting marked evi- 
dences of unconformity. One is at the base of the Cretaceous ; 
and the other is at the base of the Eocene. 
Between the Cretaceous plane of unconformity and the one 
at the bottom of the Des Aloines series (Lower Coal Pleasures) 
no notable level of unconformity is known. Sedimentation 
appears 1o be uninterrupted! through all of the Paleozoic above 
the Mississippian. Throughout all of the 3500 feet of Pal- 
eozoics represented bv the Des Aloines, JNlissouvian, Oklaho- 
man (so-called Permian) and Cimarron series, the levels of 
evident peneplanation seem wanting. In western Iowa, if 
the Ft. Dodge gypsum deposits belong to the "Permian," 
there is to be accounted for a stratigraphic interval of between 
2000 and 3000 feet, even when the nearest and lowest of the 
Kansas deposits is considered. The stratigraphic position of 
the basal horizon of the so-called Permian of Kansas is at 
the lowest calculation more than 2000 feet above Ft. Dodge. 
There are at the present time not the slightest grounds for 
