Review of Recent Geological Literature. Iai 
tors. These details, which make up the bulk of the paper, are the 
data upon which are based the author’s views on the general faunal 
correlation of the several rock layers containing the fossils discussed. 
The views expressed are of exceptional interest; for, as in the case of 
all this author’s faunal studies, the latter have to do with broad prin- 
ciples, notwithstanding local titles. 
The suggestion offered, says the author, ‘‘as an interpretation of all 
the faudal relationships is, that after the wide geographic distribution 
of the later Kinderhook faunas, from Ohio to beyond the Rocky moun- 
tains, there was a withdrawal of the fauna for some reason, within 
- the more western portion of the area it had occupied, where it conr 
tinued to flourish during the period of development of the Osage faun- 
as in the Mississippi valley. At a much later period. the beginning of 
Genevieve time, this western fauna again migrated eastward and en- 
tered into the fauna of the St. Louis limestone and its stratigraphic 
equivalents. The recurrence, in rocks of the age of the St. Louis lime- 
stone at Batesville, Arkansas, of a fauna of much older type, even 
Devonian, has been recorded by Williams, but this Batesville fauna 
seems to have migrated eastward from the southwestern region. The 
eastward migration from the northwest of the fauna containing per- 
sistent Kinderhook types, probably occurred at approximately the 
same time as a similar migration from the southwest, the evidence 
of which is recorded in the rocks of Arkansas.” 
There is one feature in the present paper to which attention 
might be called, that is, indeed, rendered all the more conspicuous 
by an absence of all mention of it. It is a very essential factor in 
the correct understanding of all Kinderhook faunas. The oversight 
is, perhaps, due largely to the fact that the author has been de- 
voting himself particularly to the study of the Carboniferous fos- 
sils. The suggestion, however, applies not to the work of this au- 
thor alone, but to nearly every one who has written on Kinder- 
hook questions. As a result of this inattention to certain factors 
there has been necessarily, though unintentionally it is no doubt 
true, a straining of the facts to fit a theory. The identification of 
the species is made by comparing them only with stratigraphically 
higher forms. Comparison with the lower species gives some very 
different results. In many cases in which this actually has been 
done, the inevitable deductions are to the effect that the closest 
affinities of many of the organic remains from the Kinderhook are 
to be found with the earlier forms rather than with the later. 
Comparisons only with the geologically higher forms tend to carry 
the “Carboniferous aspects” of the various faunas downward much 
farther than should really be done. 
It is unfortunate that the author apparently uses the term 
Chouteau in two very different senses. In one case, it refers to 
the uppermost limestone of the Kinderhook. Elsewhere it alludes 
to the faunal, or time, equivalent of the Kinderhook terrane, of 
which the Chouteau limestone forms the upper third. In the latter 
