442 THE MECHANICAL FUNCTIONS. 



usual horizontal position, the anterior extremities 

 would have had to support the whole of the enormous 

 weight of this neck and head. This peculiarity of 

 structure, however, introduces considerable modifi- 

 cations in the mode of progression of the animal. 

 The ordinary pace of the camelopard is the amble; 

 but it has also a slower walking pace, and occasion- 

 ally a gallop : in performing which last movement, 

 the hind feet are brought more forwards than the 

 fore feet, so that at that moment the fore and hind 

 limbs cross one another like the strokes of the 

 letter X. In the amble, its undulation is so con- 

 siderable as to give it the appearance of being lame. 

 A similar kind of limping gait, arising from the 

 same cause, namely, the disproportionate elevation 

 of the fore part of the spine, has been observed in 

 the HycBna. 



^ 5. Ruminantia. 



In following the series of Mammalia in the order 

 which best exhibits their successive stages of de- 

 velopement, I shall commence with those whose 

 digestive apparatus is formed to extract nourish- 

 ment exclusively from the vegetable kingdom. 

 The first assemblage that presents itself to our 

 notice is the remarkable family of Ruminants, 

 which feed principally on herbage. Wherever the 

 earth is clothed with vegetation, it requires neither 

 skill nor exertion on their part to seek and to devour 

 the rich repast which is profusely spread under 

 their feet. To remove from one pasture to another, 

 to browse, and to repose, constitute the peaceful 



