Among mammalian types obtained by the California Institute of Technology in a late Miocene fauna from the Esmeralda formation near Tonopah, Nevada,1 is a feline of the Pseudœlurus group. Fortunately, the material on which the determination is based represents several individuals and furnishes for the first time information concerning the structure of the skull and the upper dentition for this American stage in the history of the Felidae. Although the type of P. intrepidus from the Miocene of Nebraska was described by Leidy as long ago as 1858, and although this and a related species have been recorded since that time from several Miocene horizons in North America, in no instance are remains of the skull and the upper dentition available.
All the lower jaw specimens from Locality 172 are smaller than the type of P. intrepidus and are more nearly comparable to P. marshi in size. However, the . . .