REVIEWS 521 
advantage of giving conclusions which have been reached independ- 
ently it lacks the greater completeness which would have existed had 
the work been compared and adjusted in advance to publication. 
Through the details given the advancement of the whole subject is 
such as will enable a rational classification of the strata to be outlined. 
with little fear that any radical departure will be necessary in the 
future. The results are not only important as regards the state of 
Kansas but they are especially valuable in pointing out more accurately 
than ever before the stratigraphical relations between the Carbonifer- 
ous rocks of that state and those of Missouri and Iowa. ‘The Kansas 
work supplies the information heretofore lacking which enables the 
geological history of the whole Western Interior coal province to be 
made out with a reasonable degree of satisfaction. The most impor- 
tant point of all however is that the three papers furnish the facts 
which until now have been needed to outline a rational classification of 
the Carboniferous deposits of the Mississippi basin. The main sub- 
divisions are so clearly defined over the whole Western Interior regions 
that it becomes a matter of surprise and even wonderment that so 
many other and diverse lines of demarkation should have been 
selected. The systematic arrangement of the main subdivisions of the 
Carboniferous is now practically the same in Iowa, Missouri, Nebraska, 
Kansas, Arkansas, Indian Territory and Oklahoma ; and hence forward 
these states can have a uniform nomenclature so far as the upper Pale- 
ozoic formations are concerned. The minor stages of each of the major 
subdivisions or series differ in different localities. They will probably 
have to be established separately in each of the several states. Local 
members have already been named for the greater part of Kansas and 
the number and limits of similar local formations have not been 
entirely neglected in other parts of the province. 
As the outcome of the recent work, and other late investigations 
of which special mention need not be made at this time, the Carbonif- 
erous of the Continental Interior appears to be separable into four 
principal sections or series. In a general way these correspond essen- 
tially with the four old subdivisons: the Lower Carboniferous, Lower 
Coal Measures, Upper Coal Measures, and the Permian. While the 
old and new lines of separation have approximately similar positions 
they do not coincide. Moreover the old lines were vague, different in 
the different states and even in different parts of the same state. The 
new lines are sharply defined in all particulars. In the field they are 
