308 BACKBONED ANIMALS. 
The dugong is peculiar to the countries adjacent to the 
Indian Ocean. The tail is shaped like that of the whale ; 
the fore-limbs are short ; the muzzle protected by numer- 
ous stiff bristles. They attain a length of twenty-five feet, 
Fic. 333.—A, skull of female dugong; the colossal tusks in the upper jaw 
never pierce the thick, fleshy lip, although they continue to grow with 
the jaw. a, the root of the tusk; 3, the point. 2, adult dugong, show- 
ing whale-like tail. 
and congregate in herds near the mouths of rivers, brows- 
ing upon the aquatic vegetation. The tusks of the female 
are completely incased in the upper jaw (Fig. 333). 
VALUE.—Hide, oil, and bones. 
