84 BULLETIN NO. VII. 



cum. Cowper's glands absent. Dentition consisting of twelve incisors 

 (except in the Sea Otter) of similar form, four canines which are not furn- 

 ished with a sharp angle or ridges behind, a variable number of premolars, 

 and one pair of molars above and two below (except in the Honey Badgers.) 

 Anal glands secreting a strong odor always present. 



As will be seen beyond, this family contains a number of 

 quite unlike groups. Some of the Mustelidce are highly aquatic, 

 others dwell almost exclusively in trees, while many are strictly 

 terrestrial. The economic importance of the family is derived 

 from the large number of fur bearing animals it includes. The 

 ermine, sable, marten, otter, mink, etc. all are members of the 

 group. The northern hemisphere is the home of the family, 

 although there are representatives in Africa and South Amer- 

 ica. We append Dr. Gill's synopsis of the sub-families and 

 add a brief review of the group before taking up our native 

 species. 



FAMILY MUSTELIDCE. 



I. Skull with the cerebral portion comparatively compressed backwards; 

 and with the rostral portion comparatively produced, attenuated, 

 and transversely convex above; anteorbitalforamen small and opening 

 forwards. Feet with little developed or no interdigital membrane. 



A. Auditory bulla much inflated, undivided, bulging, and convex for- 

 wards; periotic region extending little outwards or backwards. Palate 

 moderately emarginated. 



1. Last molar of upper jaw transverse (with the inner ledge inflated 

 at its inner angle); sectorial tooth with a single inner cusp. 



a. Molars i; first true molar (sectorial) of lower jaw followed by a 

 second (tubercular) one. Toes short regularly arched, and with the 

 last phalanges bent up, withdrawing the claws into sheaths. 

 [Weasels] M USTELIN^E. 



6. Molars J-; first true molar (sectorial) of lower jaw only developed. 

 Toes straight, with the last phalanges and claws extended; the 

 latter non-retractile. [Honey Badgers] MELLIVORIN^E. 



#. Molars 1; last molar of upper jaw enlarged and more or less ex- 

 tended longitudinally. Toes straight with the last phalanges and 

 claws extended; the latter non-retractile. [Badgers] MELIN.E. 



B. Auditory bulla elongated and extending backward close to the par- 

 occipital process. Palate moderately emarginated. 



1. Last molar of upper jaw transverse; (with the inner ledge nar- 

 rowed inwards); sectorial tooth with two inner cusps. [Helictis] 

 HELICTIDIN.E. 



C. Auditory bulla inflated, undivided, with the anterior inferior ex- 

 tremity pointed and commonly united to the prolonged hamular pro- 

 cess of the pterygoid. Palate moderately emarginated. 



1. Last molar of upper jaw transverse; with the inner ledge com- 

 pressed. [Zorilla] ZORILLI:SLE. 



