582 The American Naturalist. [July, 
The new forms are Paleozoic, and are mostly from two new locali- 
ties—Richmond, Ohio, and Cassville, West Virginia. There are, how- 
ever, a number of new species from old horizons. 
Tables of the geographical and also of the geological distribution of 
both American and European genera are given in the introduction, 
followed by a statement of the characteristics of the Mylacridae and a 
discussion of some of the anatomical features of paleozoic cockroaches. 
In this connection the author calls attention to possible mimicry 
among these old forms of insect life, and figures side by side a cock- 
roach wing and a fern frond found associated in the same beds, to show 
how close is the resemblance between them in the general distribution 
of nervures and in outline. 
The illustrations comprise twelve page plates and three figures in the 
text. 
The Comanche Cretaceous.—Prof. R. T. Hill has found some 
outlying areas of the Comanche series in Barber and Comanche Coun- 
ties, Kansas, and in G County, Oklahoma, and in the Tucumcari re- 
gion of New Mexico. These strata are identified from paleontological 
evidence. 
The importance of a correct determination of these beds is evident 
from the following concluding remarks of the author. 
“ The geology of the outlying areas of the Cretaceous preserved in the 
scarps of the Plains adds greatly to our knowledge of the distribution, 
variation, paleontology and history of the beds of the Comanche series, 
and of the progressive oscillatory conquest of the Great Plains region 
by the sea in Cretaceous time. The Belvidere (Kansas) beds have re- 
vealed the following additions to our knowledge of Cretaceous paleon- 
tology : First, a lower stratigraphic occurrence of the dicotyledonous 
Dakota flora than known, whereby we may now say that dicotyledons 
make their first appearance before the beginning of the Washita sub- 
epoch, instead of in the Dakota as hitherto believed. Second, a simi- 
lar downward range in the geologic scale of the ichthyic vertebrates 
of hitherto supposed Upper Cretaceous range. Third, intermingling 
of these plants and fishes with molluscan species and other vertebrates 
of the Washita division such as has not hitherto been found in the 
Comanche series.” (Amer. Journ. Sci., Lol. L, 1895). 
Kolguev Island, which lies 130 miles southeast of Novaya Zemlya, 
differs, according to Col. Feilden, in geological structure, both from 
mountainous islands of its neighbor and from Russian Lapland. The | 
entire elevated region of the island is composed of beds of sand contain- 
