PLEISTOCENE VERTEBRATES FROLI CUMBERLAND CAVE 69 



it from the living species of North America, nor can it be assigned to 

 any modern form with certainty. 



The form corresponds favorably in size with specimens of both 

 0. princeps and 0. schisticeps. Although the dentition is closely the 

 same as in these Recent species, the styles or columns on the inner and 

 outer surfaces of the lower molariform teeth in a couple of the fossil 

 mandibles are slightly closer together than is common in North 

 American Ochotona. This condition sharpens or narrows somewhat 

 the inner and outer reentrant angles. 



The presence of Ochotona in the fauna is significant inasmuch as the 

 North American species are found living only in the western and 

 northwestern part of the country. The present occurrence shows the 

 pika to have been present in the Appalachian region in Pleistocene 

 time. 



The fossil record of Ochotona is very scanty. A form described by 

 Cope (1871, pp. 93-94) as Praotherium palatinum from the Port 

 Kennedy deposit may possibly be Ochotona. The Cumberland Cave 

 specimens, however, do not conform to the description given by Cope. 

 The upper molariform teeth of the Maryland Ochotona show a pro- 

 nounced external groove as in the living species and an enamel ridge 

 divides the occlusal surface of each tooth. Furthermore, the first, 

 second, and last teeth of the cheek series are structurally distinct from 

 one another and from the two intermediate teeth, as in living pikas. 

 According to Cope the four upper teeth preserved in the tooth row of 

 P. palatinum are structurally ahke; also, their external surfaces are 

 not markedly grooved and the occlusal surface of each does not show 

 a distinct median ridge. 



Family LEPORIDAE 



LEPUS cf. AMERICANUS Erxleben 



Hares are well represented in the cave collection. At least 10 skull 

 portions and 19 lower jaws are included in the material. A noticeable 

 range in size and proportions of skulls, jaws, and teeth exists, though 

 apparently within the limits of individual variation. No persistent 

 characters of importance were noted distinguishing the fossil from the 

 living hare, L. americanus. However, it is possible that some of the 

 smaller, more incomplete lower jaws may represent Sylvilagus, but 

 none of the skull portions shows the distinct interparietal and postor- 

 bital processes formed as in Sylvilagus. 



