736 CHARLES S. PROSSER 



that in the Upper Permian is, perhaps, also the horizon of the 

 upper limestones and shales of Kansas with Psendomonotis Hawni, 

 which surmount 75 meters of variously colored shales and marls, 

 with gypsum (assise de Marion de M. Prosser) .* 



It is to be noted, however, that de Lapparent is in error in 

 correlating the sandstones and shales of Nebraska with the lower 

 part of the Penjabien or Saxonien, which he classifies as the 

 Middle Permian. 2 Such a classification puts the Nebraska City 

 beds at least above the Neosho and Chase, as is clearly indicated 

 on his table of synchronism, while as a matter of fact it has been 

 shown by Dr. Beede and the writer that they are probably 

 equivalent "to the Topeka limestones and Osage shales of the 

 Kansas river section, which form the upper part of Professor 

 Haworth's Shawnee formation of the Upper Coal-measures." 3 

 The rocks included between the top of the Shawnee formation, 

 which is marked by the base of the Burlingame limestone, and the 

 top of the Chase stage have an approximate thickness of 950 

 feet in eastern central Kansas, which gives an idea of the strati- 

 graphic error when the Nebraska City beds are assigned to a 

 position above the Chase stage. 



In discussing the rank of the Permian de Lapparent wrote : 

 The marine types of the Permian, scarcely known until recent 

 years, show in Asia as in the United States greater and greater 

 development. Finally, the well confirmed discovery of Ammon- 

 ites with arborescent septae gives to the pelagic fauna of the 

 period a special character, at the same time that by the first 

 appearance of true reptiles the terrestrial fauna shows a higher 

 order than that of the preceding period. Therefore, we, agreeing 

 with the excellent arguments of Neumayr in his Erdgeschi elite, 

 raise to the rank of system this last division of Primary time. 4 



Finally, from among the other famous European geologists 

 who rank the Permian as a system and have written in support 



1 Ibid., p. 994. 'Ibid., pp. 986-93. 



3 Jour. Geol. Vol. VII, Aug., 1899, p. 346. Also, see Prosser, ibid., Vol. V, 

 March, 1897, p. 148 ; and Beede, Kan. Univ. Quart, Vol. VII, Oct., 1898, Series A, 

 p. 231 ; and Trans. Kan. Acad. Science, Vol. XVI, 1899, p. 70. 



4 Ibid., p. 964. 



