PROTOREODON 



35 



other of the species. The supraoccipital crest is somewhat less produced and the wings are spread 

 farther apart than usual. The inferior border of the horizontal ramus is convex, as in P. pumilus, 

 and is not so straight as that of P. medius. The ramus as a whole is relatively heavier. 



Fig. 9. — Protoreodon minor Scott. Skull and jaw. PLT. Cat. No. 3032 CM. Nat. size. (After Peterson, 1919.) To 



show relative size of Eocene forms. 



Dentition: P 2 is simple but not unduly compressed; P 3 has a very poorly developed posterior 

 crescent and median crest; and P 4 is very similar to that in P. pumilus but is proportionally smaller 

 and lacks the well-developed cingulum of the latter. The protoconule of the molars is smaller than 



Fig. 10. — Protoreodon minor Scott. Crown view of left superior dentition. HT. Cat. No. 11339 P.U.M. Nat. size. 



(Redrawn from Scott, 1899.) 



in Marsh's species, and the parastyles and mesostyles are less prominent; otherwise they are quite 

 similar, except for a proportional reduction in size. 



Discussion: In the reduction of the protoconule of the molars this species resembles P. medius. 

 The skull is proportionally deeper than that of the latter and differs in other ways as well. 



Protoreodon paradoxicus (Scott) 1898 

 Fig. 11; PI. I, fig. 2 



Original Reference: Preliminary note on the selenodont artiodactyls of the Uinta formation. Proc. 

 Amer. Philos. Soc, XXXVII, pp. 79-80 (A griotherium faradoxicurn) . 

 Type Locality: Mouth of White River, Utah. 



Geologic Horizon: Upper Eocene (Uinta — Hor. upper B or lower C). 

 Type: Holotype, Cat. No. 11234 P.U.M., skull, mandibles, and vertebra;. 



Specific Characters: The skull is slightly longer than that of P. parvus and has a long 

 cranium and a face that appears short, although with the orbits it is nearly half of the skull length. 



