460 



CARNIVORA 



posterior chamber, the surface smooth, the aieatus large, not 

 tubular ; width of basioccipital at middle less than that of bulla 

 in same region ; mastoid and paroccipital processes small, the 

 latter thin and plate-like, both closely applied to surface of 

 bulla. Postorbital region abruptly contracted behind postorbital 

 process, the depth of the constriction increasing with age ; 

 postorbital process vei'y large, at first triangular in outline, 

 afterward becoming ligulate, its upper surface obliquely flattened. 

 Interorbital region much constricted, its least width considerably 

 less than that of orbit. Rostrum short and deep, the distance 

 from orbit to gnathion about equal to breadth over canines and 

 slightly less than palatal depth at posterior extremity of nasals ; 

 nasal branch of premaxillary broad, its width at front of nasal 

 often nearly equal to that of nasal in same region ; anteorbital 

 foramen moderately large, opening directly forward under 

 overhanging rim of orbit and above middle of first large 

 premolar. Palate broad, triangular in outline, its width 

 including molars about equal to median length, the median 

 posterior extension slight, but usually marked oS" at each side by 

 a lateral emargination extending in some instances nearly to 

 level of middle of carnassial ; incisive foramina moderately large, 

 elliptical in outline, slightly oblique, extending from level of 

 middle of canine to middle of space between canine and outer 

 incisor ; mesopterygoid space nearly parallel-sided, somewhat 

 longer than wide, its anterior border double-concave (encroached 

 on by blunt median spine of palate) ; hamulars slender, a little 

 converging ; external pterygoid process well developed, laminate, 

 angular, much smaller than hamular. Mandible rather slender, 

 the anterior border of coronoid rising at an angle of only about 

 50°, the distance from apex of process to posterior border of 

 molar about equal to that from latter point to front of 

 symphysis ; lower profile of ramus slightly convex, though with 

 anteiior and posterior flattened regions ; angular process straight, 

 rather short, a little below level of alveolar line. 



Teeth.- — As a whole, and in comparison with that of European 

 Carnivores of other families, the dentition appears rather weak, 

 owing to the complete suppression of all crushing surfaces and 

 the consequent narrowness of the cheek-teeth. Incisors small 

 and weak, the crown area of i^, the largest tooth, about equal to 

 that of ^^ and i"^ together and scarcely more than one-eighth that 

 of canine ; upper incisors forming a continuous, straight or 

 faintly convex row separated from canine at each side by a well 

 marked diastema nearly as wide as base of canine ; i^ and z'^ sub- 

 equal, the second tooth slightly the larger, the crowns a little 

 compressed, slightly higher than wide when viewed from in 

 front, spatulate in outline, the cutting edge without cusps or 

 lobes, but a little higher at middle than at sides, posterior border 

 somewhat concave with faintly developed heel ; P with cutting 

 edge oblique, and crown more nearly terete. Lower incisors 



