382 DR. ST. G. MIVART ON THB ARCTOIDEA. [Apr. 21, 



The cranial characters have been, in the main, given by Prof. 

 Flower \ Besides these it may be noted that the outline nf the 

 skull seen in profile has a rather striking resemblance to that of 

 some of the larger Cats. The muzzle is very broad, more so relatively 

 than in any Arctoid yet noted except Conepatus and Ailurus. 



It is prolonged backwards behind the last molars, though hardly 

 more so than in Mellivora, and it has not so definite a lateral 

 boundary as in the latter, though the pterygoids show a tendency to 

 descend below the general level of the palate ". The maxilla forms 

 but a small floor to the orbit. The zygomata extend much 

 outwards, owing to the breadth of the glenoid surfaces. The sagittal 

 ridge is much as in Mellivora. The glenoid foramen is very large. 



A Flight ridge connects the paroccipital and mastoid processes, 

 and the" latter, though conspicuous, does not depend below the 

 meatus auditorius externus. The stylo-mastoid foramen is very 

 conspicuous. The infra-orbital foramen is moderate or rather small. 

 The angle of the mandible is little conspicuous and is pressed 

 upwards, though not so much so as in Arctonyx and Mydaus. 



Molar formula=P. |, M. \. 



The dentition considerably resembles that of Mellivora, as to the 

 form of teeth, not of course as to their number. 



The outermost upper incisor, however, is very large and canine- 

 like. The fourth upper premolar is relatively larger than in 

 Mellivora — especially its hindmost cusp ; the first upper molar is a 

 little more equal in length externally and internally than is generally 

 the case in the last-mentioned genus. The fourth lower premolar 

 has only one hinder cusp and that smaller — thus resembling Galiciis. 

 The first lower true molar is larger than in Mellivora. There is a 

 very small heel and no inner tubercle. There is a second true 

 molar, which is a small, rounded tooth. The dentition is very 

 sectorial, at once more sectorial and powerful than in any other 

 Arctoid. It may therefore be interesting to compare its dentition 

 with that of one or two other specially predacious carnivora. 



Gulo compared with Felis — has the incisors relatively larger. The 

 third upper premolar is rather smaller with the main cusp less 

 relatively produced, the fourth upper premolar, or upper sectorial, 

 has its ibre-cusp smaller, its hind cusp large and more equal in 

 development to the mid-cusp, and the internal cusp larger. The 

 first true molar is also much larger. 



In the lower jaw the third premolar is less trilobed than in Felis 

 and its principal lobe is less developed. The sectorial, or first true 

 molar, differs by having a large heel, and in having the two prin- 

 cipal cusps less lofty. There is a second true molar. 



Gulo compared with Hyaena and Felis. — The incisors are not so 

 large relatively as in Hycena, and the other ones are less pre- 

 ponderating. In these respects Oulo is more like Hycena than Felis. 

 The third upper premolar is much smaller relatively. The hind 

 cusp is less marked and little produced. The fourth premolar has 



1 P. Z. S. 1869, p. 12. ^ See above, p. 373. 



