new Genus of Ursidae. 129 



fore, to sever thibetamis from Treiuarctos, and to name aud 

 define it as follows : — 



Genus Arcticonus *, nov. 



Type, Ursiis thibetamis j Cuv. 



Fore foot with digital pads separated almost to their 

 proximal extremities and capable of wide divarication ; 

 digital pad of the pollex set far back, behind that of the 

 second digit. Area between the digital pads and plantar 

 pad overgrown with hair, except behind the pads of the 

 pollex and fifth digit. Carpal pad as wide as the plantar 

 pad and elongately piriform, being broad externally and 

 narrowed towards the inner, or poUical, side of the foot, 

 where it tonches the plantar pad. Elsewhere the carpal pad 

 is separated from the plantar pad by a depressed hairless 

 area of grooved and thickened skin. The wrist above the 

 carpal pad is thickly hairy. 



Hind foot resembling the fore foot in the separation 

 of the digital pads, and the hairiness of the area between 

 them and the plantar pad ; digital pad of the first and fifth 

 digits set behind those of the second and fourth, so that the 

 series is strongly curv^ed. Plantar pad forming a continuous 

 shield with only a feebly-marked depression, devoid of hairs, 

 on the inner or hallucal margin. 



Ears large. Rhinarium normal; upjDcr lip hairv, except 

 for a narrow naked strip of skin extending from the rhina- 

 rium in the middle line. 



The only species of bears which combine in their fore feet 

 free digital pads with an immense carpal pad as wide as the 

 plantar pad, and merely defined from it by a groove of naked 

 skin, are Helarctosmalay anus and Trei7iarctosoniatus and their 

 allies. Apart from the characters supplied by the subrhinarial 

 tract of the upper lip and the ears, Helarctos may be distin- 

 guished by the shortness of the skull in front of the post-orbital 

 processes, involving reduction in length of the post-canine 

 space, suppression of one of the anterior upper premolars, 

 and other features requiring analysis with con>iderable 

 material, Tremarctos also has a very short skull, much 

 shorter than in Arcticonus thibetamis. In one point at 

 least it differs from the skull of all other bears. In the 

 mandible the hollow of the coronoid pi'ocess is defined 

 below by a strong ridge passing downwards and backwards 



* apKTos, a bear, mKihp, -ovos, an imaa-e. Hence the second syllable of 

 tbe geueric uame is long, and the third short. 



An?i. & Mag. N. Hist.- Ser. 8. Vul. xx. 9 



