xix.] UNGULATA. 321 



In the Tylopoda the cuboid and navicular are distinct. 

 There is no internal cuneiform. The second and fifth digits 

 are entirely absent. The metatarsals of the third and 

 fourth are united except at their lower extremity. The 

 phalanges resemble those of the fore-foot. 



In the Tragulina the cuboid, navicular, and two outer 

 cuneiforms are united to form a single bone. The third and 

 fourth metatarsals are confluent. The second and fifth are 

 complete, extending from the small digits up to the tarsus, 

 but are very slender. 



In all the Pecora (Fig. 121) the cuboid {cb) and navicular 

 {)!) are united, as are the second and third cuneiform bones, 

 and in some 'Dqqx {Cerviihis and Piidit) these latter are further 

 united with the cubo-navicular ; the first cuneiform is always 

 distinct, though small. ^ The third and fourth metatarsals 

 {ni III. and m iv.) are united in the same manner as the 

 metacarpals, and the phalanges of the digits are very similar 

 to those of the manus. The second and fifth metatarsals are 

 always wanting ; the bones of the corresponding digits are 

 absent in the Giraffe and most of the Oxen, Sheep, and 

 Antelopes. In the Deer there are usually three small 

 phalanges to each of these digits, not directly articulated 

 with the rest of the skeleton. A large, oval sesamoid is 

 commonly present in the plantar surface of the tarsus. 



The pes of the Hyrax closely resembles that of the 

 Rhinoceros, but the ungual phalanx of the second digit is 

 cleft almost to its base. 



In the Proboscidea the pes is short and broad, but 

 smaller and more compressed than the manus, and in the 

 more rudimentary condition of the two lateral digits shows 

 a greater tendency to approach the Perissodactyle form. 



^ See Sir Victor Brooke, Froceedijigi of the Zoological Society, 1874, 

 P- 34- 



Y 



