100 The American Geologist. August, ID02. 
gypsum shales of Iowa. Moreover, it is quite certain that the 
"Red-beds" of Kansas are not all of Paleozoic age. From a 
purely lithologic standpoint, if the comparison has any value 
at all. the closest analogue of the Ft. Dodge gypsum shales 
is to be found in the nearest Tertiary deposits of the region. 
It is not at all improl^able that the Iowa gypsum may have to 
be eventually referred to so late a date ^s the Eocene. Until 
fossil data are secured there may long exist very strong 
grounds for regarding the beds in question as possibly Ter- 
tiary. 
The hypothesis of arid climate during the so-called Per- 
mian period appears to have far too slender basis to be of 
much real service in determining the possible contemporan- 
eity of the Kansas and Iowa gypsums. In fact, so far as the 
information actually acquired goes the genesis of the Ft. Dodge 
gypsum and associated shales do not demand necessarily an 
especially arid climate. Neither does the fact that fossils have 
not yet been found in these deposits argue for aridity during 
the ])eriod when the gypsum was supposed to be forming. No 
real effort has ever been made to search for fossils in shales 
overlying the gypsum. Personal examinations have led to 
the belief that the field is a favourable one for the finding of 
organic remains. The lacustrine gypsum formations of the 
Paris basin appear at first glance as uninviting for fossils as 
the Iowa beds ; but an extensive array of vertebrate remains 
has been found there, together with land shells and plants. 
Underneath, too, are other gypsum beds of marine origin, 
carrying in the associated shales a considerable fauna. 
The elaborate talkie showing the gypsum deposits of the 
world is deceptive ?o far as indicating that the principal gyp- 
sum bodies of the world are found in Permian strata. In- 
stead of the 10 great di.stricts mentioned as Permian there 
should be in reality only two. Texas, Oklahoma, Indian ter- 
ritory and Kansas practically belong to a single field m place 
of four; and some^of the most important gypsum deposits 
of these states are of later age than Paleozoic. The same 
may be said of the great Russian gypsums. 
In this connection it may be stated that it is questionable 
whether the term Permian is applicable to any American stra- 
ta. The original Permian is at best only a provincial series. 
In this country the main lieds to which the title has been given 
