ANTHRACOLITHIC ROCKS OF KANSAS 127 



is used as though it were equivalent to the series of formations 

 for which I have used the designation of Permian system. At this 

 place it is well to state that, so far as terminology is concerned, I 

 consider the Permian division as having the rank of a period in time 

 {system on the rock scale), and not that of an epoch (series on the 

 rock scale), in accordance with the usage of most of the recent lead- 

 ing American and European standard manuals of geology.^ In 

 certain papers pubhshed by the United States Geological Survey 

 or with its permission I have used the name Permian with the taxo- 

 nomic rank of an epoch or series, because required to do so by the 

 rule of the United States Geological Survey which states that "in 

 the Carboniferous, Permian, Pennsylvanian, and Mississippian " 

 are series "now recognized as applicable to North America.'"' Dr. 

 Girty uses the term "Permian epoch"^ in accordance with the rule 

 of the United States Geological Survey. If this fact be kept in mind 

 it will explain some of the differences in correlation between the 

 papers of Dr. Girty and my own. 



Concerning the lower limit of the Permian system in Kansas I 

 wrote in 1895: 



If it be considered better to put all the beds in either the Carboniferous or 

 Permian system, it might be just as well to refer the deposits generally called 

 Permo-Carboniferous to the Permian. If such correlation be agreed upon, then, 

 in Kansas, the line separating the Cottonwood and Neosho formations would 

 become the line of division between the Carboniferous and Permian systems. 4 



Furthermore, on pp. 795, 796 I continued as follows: 



Consequently we would refer the Wabaunsee and Cottonwood formations to 

 the Upper Coal Measures. The Neosho and Chase formations are transitional 



1 See Chamberlin and Salisbury, Geology, Vol. II, 1906, p. 619; Scott, Att Intro- 

 duction to Geology, 2d ed., 1908, p. 637; Geikie, Text-Book of Geology, 4th ed., 1903, 

 Vol. II, p. 1063; De Lapparent, Traite de geologie, 5th ed., Vol. II, 1906, p. 752; 

 Suess, The Face of the Earth {Das AntUtz der Erde), Sollas' translation, Vol. II, 1906, 

 p. 249 {La Face de la terre, Margerie's translation, Tome II, 1900, p. 407); Kayser, 

 Lehrbuch der Geologie, 3d ed., II. Teil, 1908, p. 256; Credner, Elemente der Geologie, 

 9th ed., 1902, pp. 367, 490; Dannenberg, Geologie der Steinkohlenlager, erst. Teil, 1909, 

 p. 42; Toula, Lehrbuch der Geologie, 1900, pp. 200, 231; Neumayr, Erdgeschichte, 

 Vol. II, 1890, p. 199; Freeh in Lethaea geognostica, Theil I, "Lethaea palaeozoica," 

 2. Bd., 3. Lief., 1901, p. 453; Koken, Die Leitfossilien, 1896, p. 550. 



2 Twenty-fourth Ann. Rept., 1903, p- 27. 



3 "The Guadalupian Fauna," op. cit., p. 42. 4 Jour. Geol., Vol. Ill, p. 793. 



