Geological Papers. . 239' 



THE CARBONIFEROUS QUADRUPEDS. 



THOSE OF KANSAS, OHIO, ILLINOIS, AND PENNSYLVANIA 



IN THEIR RELATION TO THE CLASSIFICATION OF THE 



SO-CALLED AMPHIBIA AND STEGOCEPHALA. 



By Roy L. Moodie, Assistant in Zoology, University of Kansas, Lawrence. 



npHE earliest quadrupeds known, as diverged into distinct types, 

 ^ have been called the amphibian and the reptilian. It is often 

 difficult, if not at times impossible, to draw the line between these 

 two large groups of animals. Before men had gone deeply into the 

 study of paleontology these two groups were considered small and 

 unimportant, but now that we know more than two dozen orders of 

 reptiles, mostly extinct, and some nine orders have been assigned to 

 the Amphibia, that opinion is no longer held, and we realize that 

 the amphibians and the reptiles were dominant on the earth, among 

 vertebrates, in late Paleozoic and throughout the entire period of 

 the Mesozoic. Just what constitutes a reptile and an amphibian 

 no one is so bold as to state at the present day, but we are war- 

 ranted in making suggestions as to what seems right in the light 

 of our present knowledge. On this basis we will assume the right 

 of discussing the classification of one of these large groups — the 

 one usually known as the Amphibia — which we shall see is a most 

 heterogeneous assemblage. 



The Carboniferous rocks of Kansas, Ohio, Illinois and Pennsyl- 

 vania — and I doubt not those of West Virginia, Iowa and Indiana 

 will also be found to contain them — contain the remains of verte- 

 brates which are of a higher type than the fishes. The remains as 

 they are preserved to us usually represent small creatures, although 

 we occasionally find fragments which show that larger individuals 

 existed at this time also. We will cite as instances of this the two 

 large vertebrae named by Professor Marsh as belonging to Eosaurus 

 acadianus, and a large rib to be described by the writer, a portion 

 of a large skull designated elsewhere by the writer as Macrerpeton 

 huxleyi Cope (formerly described as Tuditanus huxLeyi Cope), and 

 various fragments recently described by Case as pertaining to an 

 unknown species of Eryops^ ; as well as the large fragment of a 

 tooth which Williston described in 1897 from near Louisville of 

 this state. He was able to show from the microscopic structure of 

 the tooth that the form was an undoubted labyrinthodont, which 

 he allied with Mastodonsaurus. 



