104 bulletin of the 



175th Meeting. Februaey 14, 1880. 



Vice-President Taylor in the Chair. 



Forty-eight members present. 



The Chair announced to the Society the election to member- 

 ship of Mr. John Henry Comstock and Mr. Eben Jenks 



LOOMIS. 



The order of exercises, which had been fixed for the evening 

 according to the terms of adjournment of the preceding meeting, 

 was a continuation of the discussion of the Silver Question, but 

 priority was given to a communication by Mr. C. A. White on 



the subject op the PERMIAN FORMATION IN NORTH AMERICA. 



Dr. White began by remarking upon the practice of giving to 

 geological formations names derived from localities where tliey 

 had first been found to have peculiar development and import- 

 ance, like the Silurian and Devonian. In this way the Carbon- 

 iferous system had derived its name from the fact that in Europe, 

 where it was most studied at an early stage of geological science, 

 it contained coal and carbonaceous shales. The progress of in- 

 vestigation, however, subsequently led to the conviction that 

 really less coal is found in the Carboniferous than in other rocks. 

 In the western portion of the United States, the Carboniferous 

 formations are, as a rule, quite destitute of coal. 



Those rocks which are assigned to the Carboniferous in the 

 West have, in general, a fauna agreeing with Carboniferous fos- 

 sils of Europe and eastern America; but it appears that, in some 

 instances, the fauna found in the lower part of the series in one 

 locality, have their correlations in the upper part of the series in 

 another locality. This is explicable upon the assumption that 

 the physical condition necessary for the development of a faunal 

 group may have prevailed early in one locality and late in an- 

 other. 



Having in view these considerations, Dr. White then indicated 

 the three principal subdivisions of the Carboniferous system in 

 Europe, viz.: — 



1. Permian sandstones and shales ; 



2. Coal measures, sandstone, limestone, and shales; 



3. Lower Carboniferous limestone without coal ; 



and adverted to the fact that the two lower divisions are found 



