EXTERNAL CHARACTERS OF THE MUSTELID.E. 807 



gutter is continued as a groove up the middle line of the rhinavium 

 between the nostrils. (Text-fig. 27, K, L.) 



In Charronia the gutter is obliterated, except close to the- 

 convex lower margin of the rhinarium, which is giooved above, 

 and the upper lip is scantily hairv in the middle line, (Text- 

 fig. 27, G-l.) _ \ 



In Gcde. Mastela, and Putorius it is also obliterated or nearly 

 so, and the infranarial portions of the rhinarium are shallower. 

 In Gale nivalis the hair of the muzzle encroaches on the uj^per 

 surface. (Text-fig. 27, A-D.) 



In Plesiogale nudijyes the rhinarium is lai^ge, with a median 

 groove, deep infranarial portions, and naked above back to the 

 posterior ends of the nostril slits. (Text-fig. 27, E, F.) 



In Ictonyx, as in Putoriics, the rhinarium is lightly biconvex 

 above and mesially grooved in front, with the inferior edge 

 hoi"izontal in the middle, convex at the sides where it curves- 

 backwards ; but the infranarial portions are deeper than in Gale, 

 Mttstela, or Putorius, and this area of the rhinarium is wider than 

 the upper portion. There is no trace of gutter and the con- 

 tinuously hairy upper lip is about as deep as the height of the 

 rhinarium. (Text-fig. 29, A~B.) 



In an example of Grison furax, or an aJlied species, from 

 Brazil, the upper surface of the rhinarium is evenly rounded from 

 side to side, the groove is on the lower half of the front surface, 

 and the nostrils are wide apart. The infranarial pol'tion is deep 

 in the middle, but quite narrow laterally, where it passes beneath 

 t'le slit of the nostril ; and this nariowed piece is defined from 

 the median piece by an oblique groove. There is no trace of 

 gutter and the depth of the lip is less than that of the rhinarium. 

 Two or three specimens of Grisonplli (sp. ?) from Cordova in the 

 Argentine show individual variation in the rhinarium. In one 

 the upper surface is lightly biconvex, the median groove is 

 distinct, and there is no gutter, in the other the median groove is 

 obsolete, the upper surface is uniformly convex as in Grison, and 

 there is a very shallow gutter.- In both the infranarial portion 

 is tolerably deep and mesially angled below, but the lateral 

 portions, which in Grison pass backwards beneath the nostril slits, 

 are practically obsolete. (Text-fig. 28, A-0.) 



In Tayra harhara the upper side of the rhinarium is grooved 

 and the anterior surface deeply and widely grooved. The nostiils 

 are larger and closer together than in Grison and the infranarial 

 portions are deep both mesially and laterally, and are marked in 

 front, as in Grison, by a fine oblique groove on each side wliich 

 meets its fellow of the opposite side in the middle line above the 

 inferior angle of tlie rhinarium in front. The rhinarium is about 

 twice as deep as the upper lip, which has no gutter. (Text- 

 fig. 28, D-F.) 



The rhinarium of Taxidea recalls that of Gale, Mustela, and 

 Putorius in the shallowness of the infranarial portions and the 

 presence of the median groove. It is, however, relatively wider, 

 Proc. Zool. Soc— 1921, No. LIY. 54 



