254 University of California Publications in Geology [Vol. 7 



of the tooth, and projecting backward so that the tooth rests 

 on a triangular base double-notched posteriorly. The tooth will 

 stand when set erect on the table. The enamel of the crown 

 extends downward on the root in front to its base. All the 

 species of Squatina are essentially alike in dentition, but as they 

 are local in distribution the living Calif ornian species (Squatina 

 calif ornica) , being confined to this Coast we may indicate the 

 California Miocene species by a separate distinction. It is named 

 for Maurice Leriche of Lille. 



Family MYLIOBATIDAE 

 Genus Rhinoptera Kuhl 

 ( Zygobatis Agassiz) 



23. Rhinoptera smithii Jordan and Beal, new species. 



(Text fig. e) 



Under the name of ''Zygobatis species" Agassiz* records a 

 fragment of a tooth of this genus from Ocoya Creek. Several 

 similar fragments have been obtained at different times from the 

 Miocene of Kern County. The species seems to be abundant. 

 Only single teeth more or less broken have been found. Most 

 likely these belong to the genus RJiinoptcra rather than to 

 Aetobatus (Myliobatis) to which Jordan doubtfully refers it 

 (loc. tit., p. 119). P. Priem (Bull. Soc. Geol. France, 1911, plate 

 III. fig. 77, figures a tooth almost precisely similar from the 

 Miocene of Argentina as "Rhinoptera sp." 



The teeth from Barker's Ranch and Oil City are laterally 

 much elongated, with serrated or combdike edge. The breadth 

 of the tooth and the size of the serrations vary considerably, but 

 they must be of the same species. It is not possible to be certain 

 as to the genus to which these fragments belong, but they may 

 be recognized from the accompanying drawing. 



Some imperfect, smaller specimens of this species were taken 

 from the Eocene of Big Creek, Oregon, by Harold Hannibal. 



The species is named for Dr. James Perrin Smith, palae- 

 ontologist of Stanford University. 



* Agassiz, Am. Jour. Sci. Arts, 1856, p. 275; U. S. Pac. R. R. Surv., 

 p. 316, pi. 1, figs. 31-35. 



