322 c. R. KEYES 



AMERICAN ROCKS ORIGINALLY REFERRED TO THE PERMIAN 



Historical note. — Regarding the Permian in this country, 

 three questions are prominently presented: (i) Should the 

 Permian be recognized in America? (2) If so, what is the 

 taxonomic rank of the succession of beds referred to it ? (3) 

 What are the upper and lower limits of the terrane so called? 

 These questions are perfectly distinct, though they are usually 

 considered together. 



The introduction of Murchison's term Permian into the litera- 

 ture of American geology was due to Meek and Swallow, in 

 1858. The year previous, Hawn had collected, in central Kansas, 

 the fossils identified by them as Permian forms. The beds from 

 which these organic remains were taken form a part of an 

 extensive sequence that extends in a broad belt from eastern 

 Nebraska, through Kansas and Oklahoma, into central Texas, 

 To this province the present notes refer. 



After the first announcement of the discovery of supposed 

 Permian fossils in this region, the subject was frequently dis- 

 cussed during a period of more than a dozen years. Meek, 

 Swallow, Hawn, Shumard, Hayden, Newberry, Marcou, and 

 Geinitz, made the principal contributions. Later White and 

 Broadhead took up the subject to some extent. Recently Cragin 

 and Prosser, in Kansas, and Cummins, in Texas, added much to 

 our knowledge of the rocks in question. 



The wholly disconnected character of the work of these 

 authors is unfortunate. Except in a general way, is has been, 

 heretofore, impossible to make any satisfactory comparisons 

 between the different parts of the province. Only recently has 

 any relationship been established between the results obtained 

 by the various explorers of this region. Prosser has been chiefly 

 instrumental in giving us something tangible to work upon. In 

 connection with his own investigations, he has made a special 

 effort to bring some of the earlier acquired results into close 

 correspondence. The upper part of so-called Permian in Kansas 

 still remains rather uncertain as to its natural subdivisions, and its 

 relations to other sections. The lower part and the underlying 



