392 MR. R. I. POCOCK ON THE EXTERNAL 



The claws and pads on these three digits and on the fifth are 

 well developed, the pads being smooth. The plantar pad is very 

 different from that of Gcelogeiiys, consisting of two elements 

 opposite the interdigital spaces of the three main digits. The 

 third, or outer, element of this pad is small and circular, and has 

 accompanied the backward migration of the fifth digit. The 

 carpal pads, two in number, are narrow, indistinct behind, and in 

 contact mesially, the inner pad being larger than the outer and 

 projecting further distally. They are separated by a longish 

 area of naked skin from the plantar pad. The inner side of the 

 wrist is covered with short hair, sometimes almost naked, as in 

 Coilogenys. (Text-fig. 13, 0.) 



The hind foot is like that of Coelogenys, except that the fii'st 

 and fifth digits have entirely disappeared, the three main digits 

 axe longer, thinner, and miwebbed, the plantar pad is much 

 smaller, consisting of two larger but small pads at the base of 

 the inner and median digits, and of a very small circular pad 

 at the base of the fourth or outer digit. Assuming this pad 

 to be the homologue of the small pad at the base of the fifth digit 

 in Coelogenys, it occupies a very difierent position. The meta- 

 tarsal pad is a long way behind the plantar pad, and shows at 

 most indistinct signs of a divisional line on its inner side. (Text- 

 fig. 13, D.) 



The feet of Olmichilla are derivable from tlie type seen in 

 Ccelogenys, with the basal webbing eliminated. In the fore foot 

 the digits are thinner, with relatively larger compressed pads 

 and shoi'ter claws adapted to a life amongst rocks, but their 

 number, relative length, and disposition are similar. There is a 

 distinctly three-lobed plantar pad and a large two-lobed carpal 

 pad, which, however, is larger than the plantar pad and not 

 smaller as in Ccelogenys. The wrist, however, is uniformly 

 covered above and laterally with long hairs. The hind foot is 

 longer and thinner, and the hallux has entirely disappeared ; but 

 the remaining four digits are similarly placed, although, as in 

 the front foot, they have relatively broader pads and much 

 shorter claws. The plantar pad is two-lobed, its external element, 

 larger than in Coelogenys, has travelled up the foot in company 

 with the fifth digit and lies laterally nearly midway l^etween the 

 plantar and metatarsal pads, the latter being defined by a sulcus 

 which expands into a notch distally. A specialisation is the 

 development of fringes of longer hairs on the inner sides of 

 the second and third digits, those on the second forming a stiff 

 comb. (Text-fig. 14, A, B.) 



In general features the feet of Lagidhim ai-e like those of 

 Chinchilla^ except that the under sides of all the digits, apart from 

 the digital pads, are thicklj^ covered with hairs and the digital 

 pads themselves are compressed and furnished, as in Cerodon, 

 with a rounded median keel. The three elements of the plantar 

 pad of the fore foot are very large and in contact. Behind these 



