342 E. L. TroxeU — Palceolagus, an Extinct Hare. 



PalcBolagiis. 

 Palatine fissure opposite P^. 

 Palatine fissure very narrow. 

 Posterior nares very narrow. 

 Posterior nares opposite M^. 

 Palatal length ant. -post. 8 mm. 

 Upper tooth series with curved 

 outer border due to small P^ 



P^ narrow anterior and M^ nar- 

 row posterior. 



Mg grooved on both sides. 



Angle of ramus with narrow ex- 

 tension. 



Body of ramus deeper and 

 wider. 



Incisors begin under M^ in thick- 

 ened ramus. 



Diastema relatively short. 



Anterior to malar, no pit. 



On outer side, a fossa. 



Lepus. 

 Same position. 

 Very wide. 

 Very wide. 

 Opposite P*. 



5 mm. on a much larger stall. 

 Series with straight outer bor- 

 der. 



P--^ wide teeth, also M^. 



Mg grooved exterior. 

 Angle very wide ant.-post. 



Body of ramus slender. 



Incisors begin anterior to Pg. 



Diastema long. 

 Malar with foramen. 

 On outer side, sometimes a 

 foramen. 



Fig. 3. — Lepus. Cat. No. 01370, Y. P. M. Diagram of palatal view of 

 skull. Posterior nares, Fn ; anterior palatine foramina, Apf. Nat. size. 



Other seemingly important features which have come 

 out in the course of this study are: the presence of a 

 coronoid process on the jaw; the straight, much narrower 

 ilium; the acetabular notch (which becomes a foramen in 

 the hare) ; the thin, erect tubercle just in front of the ace- 

 tabulum for the origin of the rectus femoris (later 

 becomes flattened and oval in outline) ; the narrow head 

 of the femur (contrasted to the broad one in Lepus y with 

 the larger trochanters and the additional sharp edge 

 extending distally), and the more prominent but more 

 simple and restricted minor trochanter ; all are to be seen 

 in Palceolagus. 



