PROCEEDINGS OF THE UNITED STATES NATIONAL MUSEUM 



Issued i^?NvA,sjl^| h the 



SMITHSONIAN INSTITUTION 



U. S. NATIONAL MUSEUM 



Vol. 105 Washington: 1955 No. 3354 



THREE MIOCENE PORPOISES FROM THE CALVERT CLIFFS, 



MARYLAND 



By Remington Kellogg 



I. LOPHOCETUS PAPPUS, NEW SPECIES 



During August 1933, a section of the rostrum of a porpoise that 

 differed from the more commonly found types with elongated rostra, 

 particularly Eurhinodel'phis (Kellogg, 1925), Schizodelphis (True, 

 1908) and Zarhachis (Kellogg, 1924), was found near Governor's 

 Run, Md. Inasmuch as Cope and Leidy had applied generic and 

 specific names to vertebrae and teeth from the Miocene Calvert 

 formation, it seemed desirable to await further material before an 

 attempt was made to determine the allocation of the newly found 

 porpoise. Fortunately, the skuU, mandibles, and vertebrae of another 

 specimen were located in July 1939. A critical examination of the 

 vertebrae and teeth has convinced the writer that this form is not 

 represented among the types of previously described porpoises 

 deposited in the Academy of Natural Sciences of PhUadelpliia. 



Although the affinities of the Miocene Lophocetus are somewhat 

 uncertain, the conformation of the skull and the relationships of its 

 componental bones suggest that it is rather closely allied to the 

 Iniidae. The periotic bones of both Inia and Lipotes are highly 

 modified and exhibit slight resemblance to one another in outward 

 appearance. The periotic of Lophocetus differs in many details from 

 that of either of these Recent genera. 



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