LYSOROPHUS, A PERMIAN URODELE. 



S. W. WILLI STON, 

 University of Chicago. 



Thirty-one years ago Professor Cope described ^ briefly three 

 small and incomplete vertebrae from the "Permian" of Ver- 

 milion County, Illinois, as those of a reptile under the name 

 Lysorophiis tricarinatiis. The type specimen was figured, with 

 additional descriptions, by Case in 1899.- In a later paper ^ 

 Case recognized the same form from the Permian of Texas and 

 gave a good description and figures of the vertebra; and ribs. 

 From the peculiar coiled condition of the various intermingled 

 series of vertebrc-e which he had himself collected he concluded 

 that the animal was long and snake-like. No limb or pectoral 

 or pelvic bones have ever been detected. Associated with the 

 form but not definitely connected with the vertebrae was a frag- 

 ment of the skull of a small animal which he doubtfully referred 

 to the same species, but which he also was inclined to refer to 

 hodcctes Cope. In 1904 Broili ^ with real skull material and less 

 perfect vertebra;, reached the startling conclusion that the genus 

 showed certain affinities to the fishes, because of the presence of 

 what he thought were gular plates in the palatine region. 

 Chiefly because of their supposed presence he proposed the 

 family name Paterosaurida; for the genus, which he located in 

 the Rhynchocephalia. It is needless to say that his views of the 

 diphylectic origin of reptiles, one phylum directly from the fishes, 

 the others from the amphibians, has been received by naturalists 

 with doubt and incredulity, and are, as will be seen, wholly un- 

 substantiated by this animal. His "gular plates" were doubtless 

 merely misplaced proatlas bones. It is rather surprising that he 

 should have overlooked the almost impossible reptilian char- 



"^ Proc. Atner. Phil. Soc, 1877, p. 187. 



"^Journal 0/ Geology, V., p. 714, pi. II., ff. I2a, I2l>, I2c. 



^ Ibid., May, 1892, p. 46, pi. IX., tf. i, 2. 



^ Paleontographica, LI. 



229 



