Vol. 5] 



Mi rriam. — Felis Atrox. 



30] 



DIAG NOSTIC CHARACTERS. 

 Fills atrox Leidy, variety bt bbi. 



Felis atrox, Leidy, Am. Philos. Soc, Trans. New Ser., vol. 10, p. 

 319. 



Type specimen of Mississippi form Col. Acad. Nat. Sc. 

 Philad. Obtained in beds of presumable Quaternary age near 

 Natchez, Mississippi. Bebbi form based on specimen 14001, Univ. 

 Calif. Col. Vert. Palae., from the Quaternary of Raneho La Brea, 

 California. 



Muzzle very wide compared with the length of the skull. 

 Postorbital processes of the frontal relatively far back. Brain 

 case small. Auditory bullae small. Anterior spine of ectotym- 

 panic region extending much farther forward than entotympanic 

 portion. Occiput high and narrow. 



Coronoid process of mandible high, wide, and near medial 

 end of condyle. Masseteric fossa very deep and showing a 

 marked excavation as far forward as the middle of the inferior 

 carnassial. Symphyseal region wide inferiorly (possibly an age 

 or individual character). Anterior outline of symphyseal region 

 more nearly normal to the inferior line of the mandible than in 

 the lion or tiger. Condyles set low with reference to alveolar 

 margin. Angle produced inferiorly somewhat farther than in 

 the lion and tiger. 



Infraorbital foramen smaller than in the lion or tiger, and 

 situated a little farther hack with reference to the P 4 . Condylar 

 foramen tending to he separated from posterior lacerated fora- 

 men on one side of the skull. 



Canines relatively large, and the incisors small or set in a 

 relatively narrow space. M ] two-rooted. Inferior carnassial with 

 metaconid. and with a well-marked heel developed on the cingu- 

 lum. Protoconid of P.. and of P 4 nearly triangular in horizontal 

 cross-section. Inner ridge of the protoconid of P 4 relatively 

 prominent at the base. 



Individuals of this species of Large size. 



