SKULL AND TEETH OF MEPHITIS MEPHITICA. 201 



considerably behind the supraorbital process, just about half- 

 way from end of rostrum to occiput, and opposite the apex of 

 the mandibular coronoid, when the jaw is closed. It is a 

 gradual pinching- together of the sides of the cranium for some 

 distance, rather than an abrupt constriction at a particular 

 point. It is sometimes unsymmetrical, one side being more 

 emarginate than the other; is sometimes scarcely narrower 

 than the interorbital space, sometimes about three-fourths as 

 much. Back of this point, the skull widens rapidly to the 

 hinder root of the zygoma and mastoid; the latter being the 

 broadest point of the skull proper, separated from the former 

 by an emargination, in which lies the opening of the meatus 

 auditorius, not visible from above. From each mastoid, the 

 skull narrows in an approximately straight line backward and 

 upward for a distance, and then ends with a straight-across 

 contour, more or less emarginate on the median line. This 

 whole posterior boundary, representing the lambdoidal crest, 

 is extremely variable, not only according to age, but fortui- 

 tously. In some skulls — those with the broadest back part and 

 most flaring occipital crest — there is a deep emargiuation in 

 the middle line of the skull, boldly salient angles on either 

 side of this, and a concave outline thence to the mastoid. 

 This occipital flange hides all the parts beneath it. For the 

 rest, the top of the skull shows a sagittal crest (only in very 

 young skulls a raised tablet), well marked in all but young ex- 

 amples, forking anteriorly (at or a little in advance of the point 

 of greatest constriction) to send a curved leg outward to either 

 supraorbital process. Aside from this crest and the occipital 

 one, the general cranial surface is vaulted. The zygomatic 

 arches, viewed above, show the point of widest divergence near 

 their posterior roots, whence they gradually and regularly con- 

 verge forward with slight curve. 



Viewed in profile, the skull shows its highest point at the 

 interorbital space, whence it slopes gradually with a general 

 slight convexity to the muzzle and occipital protuberance. 

 This highest point is generally a little, sometimes decidedly, in 

 advance of the middle of the skull. The frontal profile may 

 acquire a slight concavity, and the opposite one may be 

 slightly sinuous, owing to irregularity of the sagittal crest. 

 The muzzle is cut squarely off, with an obliquity of perhaps 30 

 degrees from the perpendicular. The zygoma shows but a 

 slight upward arch, and no bevelling or special curve to define 



