AMERICAN AMPHICCELIAN CROCODILES 7 



vertebra from the supposed Benton Cretaceous of Kansas, which he 

 referred to Hyposaurus under the specific name H. vebbii or H. 

 vebbianus. The locality whence his type was obtained is such that 

 its horizon can only be the upper part of the Lower Cretaceous. 

 Cope believed at first that the form was longirostrate, and so indeed 

 it may yet prove to be. Within recent years I have recognized 

 various fragments of the skull and vertebrae of what are evidently 

 brevirostrate crocodiles from what probably is the same horizon 

 as that of the type of H. vebbii, in southern Kansas. Whether or 

 not the form or forms which they represent are conspecific with 

 H. vebbii remains to be proven, but there is no doubt of the occur- 

 rence of a brachystomous crocodile in the Comanche of Kansas.^ 



In 1878 Professor Cope described^ from the Morrison beds of 

 southern Colorado the vertebrae of a small amphicoelian crocodile 

 under the name Amphicotylus lucasii. In 18882 he collocated with 

 these vertebrae a skull and various other bones, from the examination 

 of which he reached the conclusion that the genus is identical with 

 Goniopholis Owen, confined, so far as known otherwise, to the 

 Purbeck and Wealden of England, Belgium, and northern Germany. 

 In September of 1877, a few months prior to the appearance of 

 Cope's description of A. lucasii, Professor Marsh briefly described ^ 

 a genus and species of brachystomous amphicoelian crocodiles from 

 the Morrison beds of Morrison, Colo., under the name Diplosaurus 

 felix. I doubt not that the genus is identical with Amphicotylus, 

 and, in much probabihty, the species is also identical with that of 

 Cope. Marsh, however, refused to accept the synonymy of Goni- 

 opholis, figuring his species, without comment, in 1896 ^ under its 

 original name Diplosaurus felix. He, however, never gave any 

 characters to distinguish his genus, and his figure shows, it is seen, 

 a marked resemblance to those of various species previously assigned 

 io Goniopholis, and especially G. simus Owen.*^ I have very recently 



1 Williston, University of Kansas Geological Survey, Vol. IV (1898), p. 78; Vol.- 

 II (1878), p. 391. 



2 Cope, Bulletin 0} the United States Geological Survey of the Territories, Ilayden. 



3 Cope, American Naturalist, Vol. XXII (1888), p. 1106. 



4 Marsh, American Journal of Science, Vol. XIV (1877), p. 254. 



5 Marsh, ibid., Vol. II (1896), p. 61. 



(> Owen, Fossil Reptiles of the Wealden and Purbeck Formations (1878), Supplement 

 VIII, Plate V. 



