Vol. 5] 



Jordan. — The Fossil Fishes of California. 



115 



19. Carcharodon riversi Jordan, new species. 



In the Pliocene of the Santa Monica Range, Dr. J. J. Rivers 

 has collected two fine specimens of the teeth of a Carcharodon 

 with the denticles fewer and coarser than in any other species. 



In this species, which I name for Dr. Rivers, the tooth is nar- 

 rowly triangular, nearly flat, with large root, the crown about as 

 high as broad at base. The serrations are very coarse, there being 

 thirty-five to forty denticles on the outer margin. These extend 



Fig. 14. Carcharodon riversi Jordan, a. Specimens from Santa Monica. 

 b. Specimens from Kern County, California. 



to the tip of the tooth, and are very much Larger than in our other 

 species; base of tooth without lateral denticle. One specimen, the 

 type, is from the Santa Monica Range, near Santa Monica. A 

 second tooth of smaller size is from Port Los Angeles, the locality 

 from which Dr. Ralph Arnold made collections of mollusks. Dr. 

 Arnold regards this deposit as Pleistocene, but Dr. Rivers states 

 that it is most certainly Pliocene. "It is simply an erratic chunk 

 that slid into a gully from a mass above. It belongs to a partly 



