THE PERMIAN FISHES OF NORTH AMERICA. 



INTRODUCTION. 



The fishes of the Permian of North America were described by Cope in 

 a series of papers published between 1875 and 1894. In a list of the verte- 

 brata, which he compiled in 1890, 21 species of fishes are enumerated; to 

 these he subsequently added an additional one, making a total of 22 species, 

 representing 10 genera. They are divided among the major groups as follows : 



From the data presented in the following pages it will be seen that 

 several of Cope's species are not tenable. Some of his Permian material 

 was too fragmentary for accurate diagnosis, and would better have been left 

 unnamed. But, as was his custom, he gave names to most of this material 

 in order to afi"ord a handle by which to refer to it in discussions of the fauna. 

 Moreover, Cope did not allow sufficient latitude to individual variation 

 within the species, even slight difi^erences being often regarded by him as 

 specific. Hence it is not surprising that his list of species should have 

 to undergo considerable change. A restudy of his types preserved in the 

 American Museum of Natura History, of the material in the Gurley Col- 

 lection at the University of Chicago, and also the study of some new 

 material, result in the addition of four genera to Cope's list; but the num- 

 ber of species, on account of additions and subtractions, remains unchanged. 

 These genera and species are divided among the various groups of fishes 

 as follows: 



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