12 NORTH AMERICAN MUSTELID.E. 



drical; tail lon^, conical, ta])ering, sometimes dilated, close- 

 haired; muzzle very obtuse. Highly a(]uatic in habits. Pelage 

 ^bole-colored. 



5. Exhydrin.t:. — Teeth very aberrant in general pattern, the 

 molars and premolars without trenchant edges or acute angles, 

 but tuberculous, 32 in number, and of equal number in both 

 jaws, brought about by incisors l^o '^^^ premolars 333, the ca- 

 nines and molars remaining as before. Molar of upper jaw irreg- 

 ularly oval ; back upper premolar defunctionalized as a " sec- 

 torial" tooth, and substantially similar to the molar. Propor- 

 tions of rostral and cerebral parts of the skull substantially as 

 in Lntrbuv, but rather an exaggeration of that conformation. 

 Postorbital processes moderate. Anteorbital foramen very 

 large, triangular, presenting downward and forward; the bridge 

 over it very slender. Posterior nares as in Lutrinw. Palate 

 produced far back of molars ; interpterygoid space very wide, 

 the emargination rather wider than deep. Auditory bullae, 

 periotic region, mastoids, and glenoids as in lAitriiuv. Coronoid 

 sloping backward, obtusely falcate, its apex overtopping con- 

 dyle. Hind feet with extraordinary development and ratio of 

 digits, being transformed into Seal-like flippers ; otherwise gen- 

 eral configuration and external appearance substantially as in 

 Lutrina'. Highly' aquatic and marine. 



ON THE ODORIFEROUS ANAL GLANDS OF THE MUSTELIDiE. 



Throughout this family of Carnivores are found special secre- 

 tory apparatus in the i)erincTal region, which furnish a strongly 

 odorous fluid. These glands are so highly developed, and play 

 such a part in the economy of the aniuials, that special notice 

 is to be taken of them. A classification of the 2IusteUd(v has 

 even been proposed, based chiefly upon their modifications in 

 the different genera. They early attracted attention, and have 

 long been generally known to zoologists. Quite recently a 

 French anatomist, M. Chatin, has made them a special study, 

 publishing a very important and interesting paper upon the 

 subject.* This paper, so far as it relates to the MusteJidw (for 

 the author has studied the odorous anal glands of various other 

 animals), I have translated for incorporation with the present 

 work ; under heads of the several species beyond will be found 



* Recberclies i)Our servir h Pbistoire auatomiqiiedes glaudcs odorautes des 

 ma mm if (ires. Par M.-J. Cbatin. <Auuales des Scieuces Xaturelles, 5<^ sdr,, 

 tome xix, pp. 1-135, planches i-ix, 1874. 



