DESCRIPTION OF A NEW GENUS AND SPECIES OF 

 WHxVLEBONE WHALE FROM THE CALVERT CLIFFS, 

 MARYLAND. 



By Remington Kellogg, 

 Of the Bureau of Biological Survey, United States Departm'ent of Agriculture. 



In the course of studying the collection of fossil cetaceans in the 

 United States National Museum, a cranium of an apparently unde- 

 scribed whale was found. A cursory examination revealed so many 

 features of unusual interest that it led to further comparisons and 

 a review of previously described forms. This cranium lacks the 

 rostrum, as well as the jugals, the lachrymals, the palatines, and the 

 nasals. Wliat remains, however, is fairly well preserved and clearly 

 pertains to a small mystacocetacean of a primitive type, related to 

 the Miocene cetotheres, but differing in certain important details 

 from the previously known crania referred to this group. 



The cranium belonged to a small cetacean, probably some 15 or 20 

 feet long. Obvious peculiarities are its relatively narrow and com- 

 pressed braincase, wide basicranium, parietals forming part of the 

 vertex, relatively small and flattened occipital condyles, and sub- 

 hemispherical protuberances on the lateral margins of the basiocci- 

 pital. These characters, together with features exhibited by the 

 periotic and tympanic, are sufficient to indicate its relationship to the 

 Mystacoceti. Though possessing many features in common with 

 Idiocetus and Cetotherium^ this cranium shows so many points of 

 difference that it seems worthy of rank as a distinct genus. 



PARIETOBALAENA, new genus. 



Diagnosis. — A new and interesting cetothere with large parietals 

 which meet mesially and form a short sagittal crest between the apex 

 of the supraoccipital and the f rontals ; maxillary, premaxillary, and 

 nasal sutures barely extending backward beyond level of anterior 

 margin of supraorbital plate of frontal at constriction ; orbit large : 

 temporal fossae wide; zygomatic process of squamosal relatively 

 small and slender, but apparently not extending forward to extrem- 



No. 2483— Proceedings U. S. National Museum. Vol. 63. Art. 15. 



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