ORDER UNGULATA. 



1391 



include the largest known mammals. They present the following 

 characteristic features ; those of the soft parts being, of course, only 

 known in the existing species. The nose is produced into a long 

 flexible proboscis terminated by the nostrils (fig. 1264); from which 

 feature the name of the suborder is derived. The limbs are stout, 

 with their segments placed nearly in a vertical line (fig. 1267), and 

 the proximal segment the longer. In the second segment the two 

 component bones (radius and ulna in the fore, and tibia and fibula 





N 



Fig. 1264. — Skull of the Indian Elephant {Elephas indicus). Greatly reduced, i, Tusk-like 

 upper incisors ; ;//, Lower jaw; n, Nostrils, placed at the end of the proboscis. 



in the hind limb) are distinct. In the carpus the scaphoid is 

 supported by the trapezoid, but not by the magnum, the latter 

 supporting the lunar ; while in the tarsus the cuboid articulates 

 proximally with the distal face of the navicular, but not with the 

 astragalus. In both the carpus and tarsus the component bones 

 interlock but very slightly ; the type of structure of the tarsus being 

 one step in advance of that obtaining in the Condylarthra. The 

 feet (fig. 1265) are plantigrade; there are five digits to each foot; 

 the astragalus (fig. 1265) is flat; the femur has no third trochanter; 

 the fibula articulates with the calcaneum ; and the jugal forms the 

 middle of the zygomatic arch. The brain is of large size; canines 

 appear to be always absent ; while incisors, growing from persist- 



