iVo. 2.J COPE ON MIOCENE EODENTIA. 385 



origin of this genus now so widely distributed over the earth. Species 

 of Lepus are reported by the Gervais from the Miocene (Montabuzard) 

 and Pliocene (Montpelier) of France. 



Lepus ennisianus Cope. 



This species is abundant in the Miocene beds of the John Day Eiver 

 Oregon, associated with a species which I cannot distinguish from the 

 Palaeolagus haydeni. The Lepus ennisianus exceeds the last-named species 

 in dimensions, being intermediate between it 2iii(li\iQ Palaeolagus turgidus. 



The form of the skull and character of the postorbital processes re- 

 fer this species to the neighborhood of the Lepus auduboni and L. bach- 

 mani.* The former has the general outline of that of Lepus sylvaticus, 

 with which it nearly agrees in size. The postorbital processes are free 

 and shorter and narrower than those of the L. auduboni. The supra- 

 orbital notch is insignificant, and is not bounded by either an angle of 

 the border or a process. Behind the postorbital processes the cranium 

 is narrower. The parietal region is convex in both directions. The in- 

 terorbital and base of the nasal region are flat. The middle of the su- 

 perior part of the occipital projects table-like beyond the lateral portions, 

 as in recent rabbits. The otic bulla is large and is flattend on the exter- 

 nal side. The mastoid presents some subvertical grooves. The paroc- 

 cipital process is rather short and is turned backwards at the apex. 



The mandible has much the form of that of L. sylvaticus, with cer- 

 tain differences. A slight convexity of the anterior border of the 

 ascending ramus is the only trace of coronoid process. The posterior 

 border of the same projects very little behind the condyle, and is but 

 slightly concave below that point. The inferior border of the masseteric 

 fossa terminates below the anterior border of the base of the coronoid 

 process, which is posterior to the corresponding position in L. sylvaticus. 

 Here the masseteric fossa extends as far forwards as the line of the 

 posterior part of the fourth inferior molar. 



The superior molars have the form usual in this genus. The crowns 

 are grooved on both the external and internal faces. The first has less 

 transverse extent than the others (except the sixth), and has a shallow 

 groove on the anterior iace. The sixth molar is a small and simple 

 cylinder. Of the inferior molars, the first has the greatest antero- 

 posterior diameter, while the transverse is equal to that of the others. 

 Of its external grooves the posterior is the strongest. The last molar 

 is much the smallest, and its section is a figure 8, with the widest circle 

 next to the fourth molar. The anterior column of the other molars 

 wears so as to be higher than the posterior. Its inner edge carries a 

 shallow groove, while the external edge is narrow and smooth, and 

 their alveoli terminate in a swelling below the first molar (Pm. III). 

 The groove of the superior incisors is nearer the internal than the ex- 

 ternal side. The inferior incisors are perfectly flat. 



*See Baird, Mammalia of the U. S., Pac. E. K. Surveys, VIII, p. 574. 

 25 G B 



