422 



CARNIVORA 



extension of palate longer than broad, emarginate posteriorly ; 

 mesopterygoid fossa parallel sided except for its anterior 

 convexity, its total length nearly equal to that of posterior 

 extension of palate, the slender hamulars hooked outward. 

 Mandible robust, its lower margin faintl}" convex from broad, 

 ill-defined angvdar process to middle ; coronoid process high, 

 triangular, the anterior border slightly the longest. 



Teeth. — Relatively to size of skull the teeth are robust and 

 strong, though not unusually so. Incisors as in Maries vmrte.% 

 but posterior shelf of i^ and P less developed, and P less strongly 

 contrasted in size with the two other teeth. Canines lower and 

 more robust than in Martes and enamel of lower tooth usually 

 less rugose. Anterior premolar both above and below (pm'^ and 

 pm.2) small, single-rooted, the crown area about eqvial to that of 

 outer upper incisor, the ill-developed cusp at front of crown, its 

 height scarcely equal to width of tooth. Middle ujjper premolar 



(pm^) two-rooted, compressed, the 

 outline of crown flattened-elliptical 

 when viewed from below, triangular 

 when viewed from the side, the 

 apex slightly in front of middle, the 

 height a little less than length ; 

 cingulum very slightly developed, 

 though rather evident at anterior 

 and posterior borders of crown. 

 Posterior lower premolar (p'»4) 

 essentially like pjiii-^ but larger and 

 relatively higher, its crown less com- 

 pi'essed posteriorly. Middle lower 

 premolar (pm^) intermediate in size 

 and form between prii^ and piH^. 

 Upper carnassial essentially like that 

 of Martes foina, but with inner lobe usually even more reduced, 

 anterior border of main cusp less oblique, and posterior cusp 

 slightly larger. Lower carnassial with crown nearly 2}, times as 

 long as wide, the main trenchant portion of the tooth formed by 

 the paraconid and protoconid, which are essentially similar to 

 those of Martes, though a little more compressed ; no trace of 

 metaconid ; posterior heel relatively small, its width distinctly 

 less than that of base of protoconid, its surface crossed by a low 

 but evident longitudinal trenchant ridge, the outer surface of 

 which sheers against inner surface of paracone and metacone of 

 upper molar. Second lower molar terete, flat, with slight median 

 longitudinal ridge, its crown area about equal to that of heel of 

 carnassial. Upper molar irregularly paudurate in outline, the inner 

 section slightly larger than the outer, the constriction evident 

 though not deep ; protocone low, terete, at middle of inner 

 section of tooth ; paracone and metacone small, confluent, the 

 paracone slightly larger than protocone, the metacone much 



Fig. 85. 

 Muxtela 2J"tortus. Teeth. 



