342 MAMMALIA: FER.E. LIII. 



FAMILY CCL MUSTBLID^E. (THE WEASELS.) 



Carnivora either plantigrade or digitigrade, with the toes 5-5. 

 Molars $ (rarely |:^) ; the upper and the last lower one tuber- 

 cular; seetorial premolar without tubercles; no csecum. Most spe- 

 cies provided with glands near the anus which secrete a fetid liquid. 

 Some are strictly carnivorous, while others are rather omnivorous. 

 Size usually median or small ; the largest, the Sea Otter, being 4 feet 

 long, the smallest weasels less than a foot. Mustelidae are found in 

 all parts of the earth excepting the Australian region. Some of 

 the species are aquatic, and one, Latax lutris, the Sea Otter of the 

 North Pacific, inhabits the sea, the young born in the kelp. In 

 this family are many of the most valuable of fur-bearing animals. 



a. Skull with the cerebral portion swollen backwards and outwards, the snout 

 short, high and truncate forwards; toes webbed; the feet adapted for 



swimming; teeth 36; aquatic. (Lutrince.) LUTRA, 597. 



aa. Skull with the cerebral portion posteriorly somewhat compressed, the 

 snout produced, attenuate and transversely convex above; feet scarcely 

 webbed; mostly non-aquatic. 



b. Auditory bulla little inflated, constricted; last upper molar above quad- 

 rangular, very large, with an outer cutting ridge ; claws non-retractile ; 

 fore-claws lengthened, fossorial. (Mephitinas.) 

 c. Teeth 34; tail long and bushy; anal secretion very strong-scented. 

 d. Skull not depressed, its upper outline irregularly convex; large 



skunks MEPHITIS, 598. 



dd. Skull depressed, its upper outline nearly straight; small skunks. 



SPILOGALE, 599. 

 bb. Auditory bulla much inflated, not constricted. 



e. Last molar of upper jaw enlarged, sub-triangular; toes straight 



with long, non-retractile claws. (Melince.) 



f. Body robust; tail very short; teeth 32. . . TAXIDKA, 600. 

 ee. Last molar of upper jaw short, transverse; toes short, arched, the 

 claws retractile. (Mustelines.) 

 g. Feet sub-plantigrade; body stout; tail very full and bushy; 



teeth 38 " GULO, 601. 



gg. Feet digitigrade; body slender. 

 h. Teeth 38; seetorial tooth with an internal tubercle. 



MUSTELA, 602. 



hh. Teeth 34; seetorial tooth without internal tubercle. 

 i. Pads of palm coalescent ; toes webbed, tail bushy. 



LUTREOLA, 603. 

 M. Pads of palm distinct; toes not webbed; tail slender. 



PUTOKIUS, 604. 



597. LUTRA Linnaeus. (Lat., otter.) 



1128. L. canadensis (Schreber). AMERICAN OTTER. Liver- 

 brown. L. 45. T. 15. E. N. Am., aquatic. Valued for its 

 fur. The Carolinian Otter, if distinguishable, is subspec. lataxina 

 {F. Cuvier). 



