676 REVIEWS 
to me, should be considered both in the relation of the Kansas fauna and the 
Permian fauna as individual and detached entities; in the entire faunal sequence 
of Kansas to the sequence of the Russian faunas; and, finally, in relation to the 
collateral evidence which the faunas of other sections bring to the discussion. 
The chief arguments which Mr. Prosser has advanced for the correlation 
seem to be these: The great development of Fusulina in the Russian section just 
below the Permian, paralleled by the development of the same group precedent to 
the ‘‘Permian”’ of the Kansas section; the development of Bakewellia in the 
Kansas ‘“‘Permian”’ and the typical Permian of Russia; and the development in 
the same beds of the Pseudomonotis group of shells. As to Pseudomonotis, the 
genus was introduced in the Kansas section considerably before the ‘‘ Permian.” 
The abundance with which it occurs at about the horizon of the Kansas ‘‘ Permian” 
appears to me a subordinate matter. Again, after critically examining the best 
specimens of Bakewellia which could be obtained, I have been brought to entertain 
serious doubts as to their generic identity with the Bakewellias of the English 
Permian as represented in King’s monograph. The dentition appears to be 
different and they seem to lack the characteristic series of ligamentary pits. 
The statement of the early appearance of Pseudomonotis in the Kansas 
rocks is true, although it had not been noted when Prosser’s statement 
was made in 1895, but it is very remarkable that this fact should be used 
as an argument against the youth of the higher beds in which it is abundant 
and characteristic. "The same could be said of other Kansas fossils, but 
I regard it as an indication of the relative youth of the Kansas deposits, 
rather than their antiquity. Some of the species referred to bakewellia 
probably belong to Jakowlew’s genus Cyrtodontarca from the Permo- 
Carboniferous of southeastern Russia, while the others may be closely 
related to them. The Coal Measures rocks of the world, so far as I am 
aware, nowhere exhibit the faunal assemblage of these shells and the 
associated pelecypods found in these strata in Kansas. 
As to the occurrence of the Fusulinas referred to above, it would seem 
to be the strongest possible evidence in favor of the homotaxy of the deposits. 
The differences pointed out by Dr. Girty—mentioned later—between the 
Kansas species and those of Europe are, perhaps, not so important as he 
supposes. In fact the Fusulinas from many of the Kansas horizons, were 
sent by St. John to Moeller who carefully studied them and referred them 
to European species. After studying the Fusulinas from practically all 
the horizons above the Oread limestone in Kansas the late Dr. Schellwien’s 
letters are decidedly positive, not to say emphatic, on these points and 
opposed to Dr. Girty’s views. 
It might also be pointed out that just below the Artinsk a zone in the Russian 
section is characterized by the profusion of Schwagerinas occurring associated 
