HOW ANIMALS EAT. 69 
rel has two in each jaw, but remarkably developed; the 
Ox has'none in the upper jaw, and the Elephant none in 
the lower; while the Sloth has none at all. 28 The canines , 
so called because so prominent in the Dog, are conical, 
and, except in Man, longer than the other teeth. They 
are designed for seizing and tearing; and they are the 
most formidable weapons of the wild carnivores. There 
Fig. 34.—Skull of the Babirusa, or Malayan Hog, showing growth and curvature of 
the canines. 
are never more than four. They are wanting in all Ro¬ 
dents, and in nearly all herbivorous quadrupeds. The 
molars , or grinders, vary greatly in shape, but closely cor¬ 
respond with the structure and habits of the animal, so 
that a single tooth is sufficient to indicate the mode of 
life and to identify the species. 27 In the Ruminants, Ro¬ 
dents, Horses, and Elephants, the summits of the molars 
are flat, like mill stones, with transverse or curving ridges 
