342 DR. ST. G. MIVART ON THE ARCTOIDEA. [Apr. 21, 



enclose the alisphenoid canal, and, almost from its apex, a strong 

 column of bone which runs backwards, extending behind the foramen 

 ovale, which it quite converts into a canal. The auditory bulla, 

 although, from the flat surface which it presents, it scarcely merits 

 the name, yet may be perceived to show the same essential character 

 as in the Weasels, which is, that it rises suddenly on the inner side 

 at once to its greatest prominence, and is then flattened off towards 

 the meatus, which is rather prolonged. The course of the internal 

 carotid artery, as indicated by the canal excavated for it in the bone, 

 is as follows : It enters by a true canalis caroticus excavated in the 

 bone of the ear, commencing quite behind, in the same fissure in 

 which open the foramen jugulare and the aperture, through which 

 the nervous vagus issues i'rom the skull, and, extending forwards in a 

 slightly arched direction, again emerges anteriorly, and, curving 

 round, enters the cranium in a backward direction, through a round 

 foramen between the sphenoid bone and that of the ear, close to the 

 aperture from which the Eustachian tube would issue, and corre- 

 sponding to the foramen lacerum anterius ; there is a distinct fora- 

 men glenoideum, although opening rather more inwardly than 

 usual ; the mastoid and paroccipital processes are both largely deve- 

 loped, and, owing to the very slight projection of the auditory bulla, 

 stand out very distinct and prominent , the foramen condyloideum 

 anterius occupies an exposed situation ; the foramen condyloideum 

 posterius I have never seen in any skull but the human, and here 

 it is said to be sometimes wanting. The characters presented by 

 the lower jaw in the Bears are essentially those most usual, though 

 not quite constant, among the Weasel group ; the angular process 

 is pushed up very near to the condyle, and much flattened beneath ; 

 the form of the coronoid process is somewhat that of the true 

 Weasels, but owing to the jaws being in the Bear more pushed 

 forwards, relatively to the situation of the cranial cavity, than in the 

 Weasels, this process is more pushed backwards to meet the temporal 

 muscle. With regard to the little process projecting beneath and 

 anterior to the angle of the jaw, it is a mere superaddition, which 

 appears again in Cercoleptes, as also in Otocyon and Nyctereutes, 

 when it has the form of a large vertical lamella, projecting from the 

 lower surface of the jaw ; it is also seen like a second angular pro- 

 cess in the Seal, so that I should not feel incliued to assign to it 

 more than a generic value. 



" In the Mustelina the pterygoid appendages very seldom manifest 

 any tendency to form a fossa, although in many sfiecies the outer 

 surface is rough and marked with ridges for muscular attachment ; 

 from behind is continued most usually a ridge which runs backwards 

 and outwards along the lower and posterior mar-gin of the foramen 

 ovale. This group is constantly marked by the entire absence of 

 the alisphenoid canal. In the remaining characters this group pre- 

 sents no essential difference from the Bears ; the commencement of 

 the canalis caroticus is usually near the middle of the inner side of 

 the auditory bullae, and anteriorly the vessel does not again quite 

 reach the outside of the cranium, simply showing itself at the 



