12 



In the lower jaw, the back molar, as usual, is small, simple, circular,, 

 single-rooted, with a central depression and irregularly-raised margin. 

 The next molar is much the largest of the series, and very notably dif- 

 ferent from the same tooth in Musteliiue. It is fairly sectorial through- 

 out ; for the back portion, though lower than the rest, is decidedl}^ of 

 the same character as the other part. This tooth consists of five cusps : 

 a posterior pair, side by side, inner and outer, of equal size and similar 

 shape; a middle pair, side by side, the outer of which is larger and 

 sharper than the inner ; and a single anterior cusp. The latter forms, with 

 the exterior middle cusp, the main trenchant edge of the tooth. The 

 interior middle cusp is a higher development of the " heel," more or less 

 prominent on the iuuer face of the main cusp of the musteline tooth. 

 The posterior pair of cusps is the low tuberculous part of the tooth in 

 Mustelina'. The first premolar from behind is a simple conical cusp, two- 

 rooted, with evident heels, both before and behind, and a well-marked 

 cingulum. The next tooth is similar, but smaller, with less of a girdle, 

 and scarcely an anterior heel. The anterior premolar is like the last, 

 but smaller still, and single-rooted. I have not seen its abortion. In 

 very old skulls, the two molars become ground almost perlectly flat, and 

 the premolars become stubby cones. The lower canines are shorter, 

 relatively stouter, and more curved than the upper ones ; there is usually 

 quite an elbow at the point of greatest curve. The inferior incisors are 

 more nearly of a size than is usual in Mnstelhuc, and more regular, i. e., 

 none are crowded out of the general plane; but this is a matter of de- 

 gree only. The outer pair is larger than the rest ; viewed from the 

 front, they widen from base to tip, and the apex is emarginate. The 

 next pair sets a little back from the general plane ; for, though their faces are 

 generally quite flush with the others, yet their greater thickness causes 

 them to protrude behind. All the under incisors are approximately of 

 one length. The cutting-edge of the outer pair is oblique; of the others^ 

 horizontal. The cutting-edge of the outer pair is nicked, as already said ; 

 and the front faces of the rest are marked by a sulcus ending in a 

 slight bilobation of their cutting-edges. 



SPILOGALE PUTORIUS, Cones ex Linn.* 



Mephitis zorilla, hicolor or interrupta of late authors. 



Numerous specimens before me, labeled "&ico?or"and '•'-zorilla,''^ exhibit 

 surprising variation in size and shape, without, however, warranting 

 presumption that they are not all of the same species. Independently of 

 the usual differences according to age, there is a remarkable range of 

 variation in the width and depression of the skull behind and devel- 

 opment of the occipital crest. An average specimen is selected for 

 description, in which the range of variation will be also noted. Com- 

 parative expressions used have reference to the skull of MeiMtis 

 mephitica. 



The skull is smaller than that of M. mepMtica; excepting one abnor- 

 mally large example, all are much less in every dimension than the 

 smallest (adult) skulls of M. meplutka which I have seen. Viewed from 

 above, the muzzle appears more tapering, if not also relatively shorter; 

 the angle of obliquity of truncation of the nasal orifice is much the 

 same. Supraorbital processes are small, but well defined, as acute 

 eminences, prolonged from well-defined ridges of bone divaricating from 

 the sagittal crest. This crest is a single and acute ridge in adult 



''Viverra piitorius, L., Syst. Nat.,i, 10th ed., 1758, p. 44. (Based on Catesby. ) 



