REVIEWS 523 
mination of the formations of the upper half of the upper Coal Meas- 
ures has been reserved for subsequent consideration. The summit of 
the upper Coal Measures is placed some distance above the top of the 
Cottonwood limestone. ‘The divisions between the Permian and the 
Coal Measures has not been located definitely and will probably be 
placed not more than 100 feet above the Cottonwood Falls limestone, 
as the palzontologic evidence upon which such a division must depend 
seems to show that the greatest change of marine invertebrate life 
occurs not long after the formation of the existing fossiliferous shales 
lying above the Cottonwood Falls rock.” 
Paragraphs are given on the ratio of the limestone to shale and 
sandstone, on the characteristics of the limestones and sandstones, on 
the inclination of the strata, on the origin of the shales and on the 
general conditions of deposition. Two subordinate papers are attached 
which are in reality parts of the one under consideration. The first is 
on the division of the Kansas Coal Measures and the other on the coal 
fields of Kansas, in which are described the stratigraphical locations of 
the various coal beds in the different formations. There is also a con- 
sideration of the physical and chemical properties and the commercial 
values of the coals. 
Although no special review of Professor Prosser’s contribution is 
here necessary, as it appeared in the JOURNAL OF GEOLOGY, it should be 
mentioned for the sake of completeness. The most important fea- 
ture perhaps, is the determination of the line of separation between 
what has been heretofore called the Upper Coal Measures and the Per- 
mian, the horizon selected being the fossil-bearing shales lying imme- 
diately over the Cottonwood limestone. The various subordinate 
formations are very clearly defined and fully described. 
In Professor Cragins’ account of the Permian system of Kansas a 
number of new names are proposed. Although Professor Prosser’s 
work is noted and some quotations made it is not clear just what the 
relations are of the subdivisions proposed by the two authors. The 
following is the scheme suggested : 
Cimarron Series. 
Kiger division. 
Big Basin sandstone. 
Hackberry shales. 
Day Creek dolomite. 
Red Bluff sandstones. 
Dog Creek shales. 
