DIAGNOSIS. OF A NEW GENUS: AND .SPECIES OF 
FOSSIL SEA-LION FROM THE MIOCENE 
OF OREGON 
By FREDERICK W. TRUE, 
HEAD CurATor, DEPARTMENT OF BioLocy, U. S. Nationat MusEumM 
At the suggestion of Mr. Wm. H. Dall, the National Museum 
purchased from Mr. B. H. Cammann of Empire City, Coos County, 
Oregon, in 1898, a portion of a large fossil skull from the soft 
Miocene sandstone of that locality. The specimen, as I am informed 
by Mr. Dall, was found by Mr. Cammann in the sandstone bluff 
on the east side of the lower part of Coos Bay, between Empire 
City and the “south slough,” in the formation to which Mr. J. S. 
Diller has given the name of the “ Empire Beds.” 
Upon examination, the skull proves, as Mr. Cammann had sup- 
posed, to be that of a sea-lion. It represents a genus allied to 
Eumetopias, but much larger. The fragment consists-of the brain- 
case, or cranium proper, together with the pterygoids and the 
palatines as far forward as the posterior end of the hard palate. 
Both zygomatic processes of the squamosal are broken off near 
the root, and the right parietal bone has been lost, leaving a large 
opening through which the whole interior of the brain-case can be 
examined. The tympanic bullz are crushed and splintered off down 
to the level of the basioccipital and so mingled with the matrix that 
their form is lost. The surrounding foramina are also obliterated, 
and the base of the skull thus presents a broad, nearly flat surface, 
the appearance of which is, at first sight, very misleading. In other 
respects, however, the fragment is in an excellent state of preserva- 
tion, and presents characters which plainly indicate its affinities. 
It has been deemed desirable to publish the following diagnosis and 
measurements in advance of a full description, with figures, which 
will appear later in one of the publications of the U. S. Geological 
Survey. 
PONTOLEON new genus 
Similar to Eumetopias, but with the ventral surface of the basi- 
occipital nearly plane, and the dorsal surface strongly concave. 
Postglenoid process of the squamosal strongly produced distally and 
directed somewhat posteriorly, so that the glenoid fossa is broader 
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