1919] Merriam: Tertiary Mammalian Faunas of Mohave Desert 517 



The upper dentition is not well shown in any of the Barstow 

 specimens. No. 23129 (fig. 95) represents a single upper molar and 

 no. 21562 (fig. 97) a portion of a lower jaw. 



BOVIDAE 



Remains of Merycodus are among the most common fossils found 

 in the Miocene of the Barstow syncline. Fragments of horns or antlers 

 are the most commonly recognized parts, and several hundred have 

 been collected in the work on the Barstow fauna. 



Figs. 113 to 117. Merycodus necatus? Leidy. Antlers, X %. A second species 

 possibly represented. Fig. 113, no. 22496; fig. 114, no. 22497; fig. 115, no. 22495; 

 fig. 116, no. 22498; fig. 117, no. 21488. Barstow Miocene, Mohave Desert, Cali- 

 fornia. 



The forms commonly seen correspond most closely to Merycodus 

 necatus described by Leidy from the Upper Miocene of the Great 

 Plains region and figured by Cope from the Santa Fe region. A 

 second form, Merycodus ( ?) coronatus found in the Barstow repre- 

 sents a peculiar type which seems to the writer to be nearest to 

 Merycodus. It may represent a distinct genus or is possibly a sport. 



MERYCODUS NECATUS? Leidy 

 This species is one of the common and characteristic forms of the 

 Barstow fauna. It is known by abundant antlers, a large portion of 

 a skull, numerous parts of jaws with teeth, and many portions of the 

 skeleton. 



The antlers, as shown in figures 113 to 117, vary from large 

 specimens with the tines dividing nearly evenly and relatively high 



