338 C. R. KEYES 



If one were to attempt anew to classify the upper Paleozoic 

 deposits of eastern Russia, following the criteria that we have 

 adopted in this country, he would have no hesitancy in assigning 

 to the Permian of that region the rank of a series, and make it a 

 subdivision of the Carboniferous. There is, however, a strong 

 possibility of three or more well marked members being recog- 

 nized in the original Permian succession, the rank of each of 

 which is certainly higher than that of stage. The uppermost, or 

 Tartaran, division is an example. This may prove to be Triassic 

 in age. The inevitable tendency to advance the rank of such 

 divisions, with the progress of knowledge regarding them, makes 

 it almost certain that the divisions mentioned as having the same 

 rank as the Tartaran, will be eventually regarded as series. 

 Permian will then have to be either advanced to the rank of 

 system, or to a new order intermediate between system and 

 series. The latter course is manifestly not only unnecessary, 

 but undesirable, and according to our present principles, 

 unnatural. The former course is of very doubtful utility, and 

 not feasible on account of the almost universal apathy on part 

 of geologists to increase the present number of recognized sys- 

 tems. When the time comes to regard the present divisions of 

 the original Permian as distinct series, Murchison's term will be, 

 in all probability, quietly dropped. It would appear then, that 

 all things considered, the original Permian can be at best only 

 regarded as a series, and a part of the Carboniferous. The term 

 like many others will then only have an historical significance. 



Subdivisio?is of the so-called Permian beds of the Mississippi 

 valley. — Most Americans, who are at all familiar with the sub- 

 ject, are inclined to regard the beds referred to the Permian as 

 forming a main division of the Carboniferous. The text-books, 

 as a rule, express this view also, and subdivide the Carbonifer- 

 ous system into three parts, the Sub- or Lower Carboniferous, 

 the Coal Measures, and the Permian. With the recent general 

 adoption of the more systematic method of stratigraphic nomen- 

 clature and a tendency to impart technical exactness by the use 

 of geographic names, the first named division in this region has 



