346 CALIFORNIA ACADEMY OF SCIENCES. 



VERTEBRATA. 



Class PISCES. 



Order ELASMOBRANCHII. 



Suborder SELACIIII. 



Family TRYGONIDiE. 



Genus Urolophus. 



408. Urolophus halleri (?) Cooper. 



Two stings of this species (one of the common Sting-Rays of the California 

 coast) were found in a perfect state of preservation in the upper San Pedro series at 

 San Pedro. Dr. C. H. Gilbert, who identified the specimens, said that owing to the 

 insufficiency of the evidence offered by the sting alone he was unable to make a 

 definite specific determination. 



Pleistocene. — San Pedro (Arnold). 



