REVIEWS 75 



the earth can fix nomenclature until all evidence has been thoroughly 

 sifted. 



In discussing the nomenclature of the Upper Carboniferous system, 

 Professor Prosser falls into the same error that he has previously, notwith- 

 standing the fact that his statements have been corrected, and he further- 

 more does not appear to have yet grasped the points of that contention. 

 However, as these are taken up in another connection, they need not be 

 considered in detail here. If he recognizes, as he states, the uppermost 

 series of the Carboniferous as the Permian, it seems wholly unnecessary 

 to say the least, to enter into a prolix argument as to whether Oklahoman 

 series and Cimmaron series are correctly determined or not. Taking the 

 first-mentioned position, most persons would pass the second over without 

 argument. The fact that the last-named terms are re- argued by him at 

 length would appear to indicate that the author is not so sure, after all, that 

 they are not valid. 



As to the dividing line between the Permian and Upper Carboniferous 

 it is stated that — 



it is clearly shown by Beede and Sellards that the Wreford limestone is a conspicu- 

 ous formation which may be readily followed from southern Nebraska across 

 northern and central Kansas, at least into the southern part of the latter state. 

 This is fortunate in case the Wreford limestone be considered the base of the Per- 

 mian, because it will afford a marked lithologic break for the line of division between 

 the Permian and the Carboniferous. 



Slimming up the main features of these papers, it appears (i) that in 

 Kansas there are recognizable in the Carboniferous section, which is more 

 than 2,000 feet thick, four well-defined subdivisions; (2) that the lines 

 of separation of these major members are essentiahy those which have 

 been located before and generally agreed upon by those who have 

 worked in the Kansas field during the past decade; (3) that the only 

 matter to be now settled is one of nomenclature — the application of simple 

 geographic names to provincial series. There have been a sufficient 

 number of titles already proposed, which cover very closely, if not quite, 

 the subdivisions recognized. The time is ripe to do away with all petty 

 technicalities, and adopt permanent names. This may easily be done even 

 at the risk of modifying somewhat the original meanings; such a course is 

 far more preferable than the proposal of a new set of titles, which in the 

 end are likely to become synonyms. 



In the articles mentioned ■ above numerous references are made to 

 the general Carboniferous section and to sections so widely separated 

 as Pennsylvania and New Mexico. Without intervening sections or some 



