406 MR. R. I. POCOCK ON THE EXTERNAL 



From the above-given description it is clear that the feet of 

 Ailurus differ very materially from those of all the American 

 genera, to which it is supposed by some authors to be. tolerably 

 closely allied. 



The feet of Ailuropoda differ from those of Ailurus and of the 

 American genera in being essentially Ursine in three par- 

 ticulars: — (1) The fore and hind feet are approximately equal in 

 length, owing to the shortening of the hind ; (2) the five naked 

 digital pads form a slightly curved transverse line, the second 

 and fifth lying respectively alongside the third and fourth, and 

 the first (pollical and hallucal) touching the second when the 

 digits are in contact ; (3) the plantar pad is a wide naked trans- 

 verse cushion, at least twice as wide as long and separated from 

 the digital pads by a short area overgrown Avith hairs. 



The fore foot further resembles that of Ursus and Euarctos in 

 possessing a large carpal pad separated from the plantar pad by a 

 long area overgrown with hair ; but it differs from the fore foot 

 of all the Uvsidse in the marked preaxial projection of the 

 plantar pad beyond the line of the pollex. This gives additional 

 width to the foot, and is doubtless correlated with the great 

 development of the radio-carpal bone, described by Lankester, 

 which simulates an additional metacarpal. The hind foot differs 

 from that of the typical Ursidse in that the entire sole is covered 

 thickly with hair from the calcaneum to the plantar pad. It 

 must be remembered j however, in this connection that in 

 Thalarctos the corresponding portion of the foot is hairy, the 

 metatarsal pad being reduced to a comparatively small lozenge- 

 shaped area. The skeleton of the digits differs from that of. the 

 UrsidaB, as Lydekker pointed out, in the presence of a bony hood 

 at the base of the terminal phalange. In the latter particular, 

 as in the remoteness of the carpal pad from the plantar pad, the 

 feet resemble those of Ailurus, but they differ therefrom in the 

 large size and exposure of the pads and in the alignment of the 

 extremities of the digits. 



Excluding those of Ailuropoda, the characters of the feet may 

 be summarized as follows : — 



a. Soles of feet entirety and thickly covered with woolly hair con- 

 cealing the pads, which are reduced in extent and thickness to 

 apparently functionless areas of naked skin ; carpal pad a minute 



naked area rem ote from the plantar pad Ailurus. 



a'. At least the digital, plantar, and carpal pads naked and well deve- 

 loped ; carpal pad, or pads, comparatively large and in contact 

 with the plantar pad, or nearly so. 

 b. Area between digital and plantar pads hairy ; carpal pad single, 

 much narrower than plantar pad ; metatarsus covered with 



hair down to plantar pad Bassariscus. 



b'. Area between digital and carpal pads naked ; carpal pads double, 

 conjointly as wide as plantar pad ; at least a small naked area 

 on metatarsus above plantar pad. 

 c. Naked area of metatarsus reduced to a comparatively small 



patch, narrowing above Jentinhia. 



c'. Naked area of metatarsus extending over the greater part of 

 that area. 



