1895.] 135 [Cope. 



Fourth Contribution to the Marine Fauna of the Miocene Period of the 



United States. 



By E. D. Cope. 



{Read before the American Philosophical Society, Apiril 5, 1S95.) 



The three preceding "Contributions" appeared ia ihe Proceedings of 

 the Acadtmy of Natural Scie?ices of Philadelphia for the years 1867, 1868 

 and 1869 respectively. Their subject matter is almost exclusively confined 

 to the description of the remains of Cetacea which occur in the marine 

 deposits of middle Neocene age of the Atlantic coastal region, and more 

 exactly, in the Yorktown formation of Dana, or the Chesapeake forma- 

 tion of Darton and Dall. The present paper continues the description 

 of these forms preliminary to an illustrated memoir on the subject. The 

 word "marine " has been introduced into the title to distinguish the series 

 from the numerous papers which have appeared on the paleontology of 

 the lacustrine neocenes of the West. For the sake of uniformity the term 

 Miocene is retained. 



PHYSETERID^. 



PaUACETUS MEOrATLANTIODS, Sp. nOV. 



The genus Paracetus has been recently proposed by Lydekker* to 

 include members of this family which possess a well-developed series of 

 teeth in the (?) premaxillary and maxillary bones. It is up to the present 

 time represented by one species, the Paracetus pouc7ietii Moreno, of the 

 Santa Cruz bed of eastern Patagonia, of the district of Chubut. Tlie 

 present species is apparently not distaatlj' related to that one. 



This genus stands near to Cogia Griy, and can scarcely, with present 

 information, be referred to a distinct family. The presence of superior 

 teeth cannot alone be regarded as necessitating this course, as they occa- 

 sionally occur in Cogia. Thus in C. sima Owen, from the coast of India, 

 there are two teeth at the anterior extremity of the upper jaw, and a male 

 of a rather small species preserve.! in the U. S. National Museum from 

 the eastern coast of the United States exhibits the same character.! A 

 male in the Museum of the Wistar Institute of the University of Pennsyl- 

 vania:): from the coast of New Jersey at Sea Isle City, has no teeth in the 

 upper jaw. The genus Paracetus seems to me to be only distinguishable 

 from Cogia by the posterior extension of the tooth series to the posterior 



* Anales del Museo de la Plata : Paleonlologia Argentina ; II : Cetacean Skulls from Patagonia, 

 p. 8, Plate iii. 



t For the opportunity of examiaing this specimen I am indebted to Dr. Goode, Director 

 of the Museum. 



X My thanks are due to Prof. Horace Jayae, Director of the Wistar Institute, for the 

 opportunity of studying this specimen. 



