UNGULATA 



direction is more irregular. Like the similar but less developed 

 air-cells in the skulls of many other mammals, they all communicate 

 with the nasal passages, and they are entirely secondary to the 

 original growth of the bones, their development having scarcely 

 commenced in the new-born animal, and they gradually enlarge as 

 the growth of the creature proceeds towards maturity. The nasal 

 bones are very short, and the anterior narial aperture is situated 

 high in the face. The zygomatic arch is slender and straight, the 

 jugal bone being small, and forming only the middle part of the 

 arch, the anterior part of which (unlike that of typical Ungulates) is 



Fig. 180.— A vertical section of the skull of the African Elephant (Elephas afric(nvs) taken 

 to the left of the middle line, and including the vomer (Vo) and the mesethmoid (ME). 

 an, Anterior, and pn, posterior narial aperture. T ' 2 natural size. (From Flower's Osteology of 

 the Mammalia.) 



formed only by the maxilla. The maxillo-turbinals are bat rudi- 

 mentary, the elongated proboscis supplying their place functionally 

 in warming and clearing from dust the inspired air. 



The neck is very short. The limbs are long and stout, and 

 remarkable for the great length of the upper segment (especially 

 the femur) as compared with the distal segment, the manus, and 

 pes. It is owing to this and the vertical position of the femur that 

 the knee-joint in the hind leg is placed much lower, and is more 

 conspicuous externally than in most quadrupedal mammals ; and 

 this having been erroneously compared with the hock-joint or ankle 

 of typical Ungulates, the popular fallacy that the joints of the 

 Elephant's leg bend in a contrary direction to that of other mam- 

 mals has arisen. There is no round ligament in the hip-joint, or 

 third trochanter to the femur. The radius and ulna are distinct, 

 though fixed in a crossed or prone position. The fibula also is 



