DIAGNOSES OF NORTH AMERICAN SUBFAMILIES. 11 



number (in the North American genus); Pm. g^j; the number 

 unequal in the two jaws, J^; incisors, canines, and molars as in 

 the hist. Mohir of upper jaw trianguUir,.the long side postero- 

 exterior. Posterior upper premohir substantially as in MepliltiMC. 

 Eostral portion of skull as in the foregoing; cerebral portion 

 conical, rapidly widening backward, with nearly straight lateral 

 outlines. Postorbital processes moderately well developed. 

 Anteorbital foramen large, subtriangular, i^resenting vertically. 

 Posterior nares as in Mephitince. Bony palate produced back 

 of the molars, as in 3fusteUn(c. Auditory bullie very highly 

 inflated, with little constriction across the short tubular portion. 

 Periotic region much as in MusteUnw, the paroccipitals close to 

 the enormous bulhie. Mastoids moderately developed, outward. 

 Glenoid fossa very deep, with prominent anterior as well as 

 posterior walls, at length locking in the condyle. Coronoid 

 process as in the foregoing. Feet with ordinary development 

 and ratio of digits, not webbed. Body stout, extremely de- 

 pressed; tail short, stout, flattened; size medium; snout some- 

 what hog-like. Progression plantigrade. Terrestrial and highly 

 fossorial; fore claws highly developed. Perinseal glands mod- 

 erately developed. A peculiar subcaudal pouch. 



4. LuTRiNJE. — Teeth of ordinary Carnivorous pattern, 36 in 

 number; Pm. ^^; the number equal in the two jaws, ~; incisors, 

 canines, and molars as before. Molar of upper jaw quadrate. 

 Back upper premolar substantially as in Mephitince and Melince. 

 Eostral ])art of skull extremely short, bringing the fore ends 

 of the nasals nearly or quite opposite the anterior root of the 

 zygoma, the sides of the rostrum erect, the top flat. Cerebral 

 portion of the skull much swollen backward, with strongly convex 

 lateral outlines. Postorbital processes variable (highly devel- 

 oped in the North American species, slight or wanting in some 

 others). Anteorbital foramen very large, presenting obliquely 

 downward as well as forward, circumscribed above by a very 

 slender maxillary process. Posterior nares as in Mustelinw. 

 Bony piUate produced far back of molars. Auditory bullae very 

 flat. Periotic region expanded, removing the paroccipitals from 

 the bulliP, but the surface not horizontal as in Mephitiniv^ but 

 very oblique. Mastoids highly developed, downward. Glenoid 

 much as in Melincv, deep^ sometimes locking condyle. Coronoid 

 as in the foregoing. Feet with ordinary development and ratio 

 of digits, which are fully webbed. Claws variable, sometimes 

 rudimentary or wanting. Body stout, but elongate and cylin- 



