CLASS MAMMALIA 



673 



Fig. 540. -- The African elephant, Loxodonla africanus. 



after Baker.) 



(From Beddard, 



Order Sirenia. — Sea-cows. — This order contains four species 

 of manatees (genus Manatus) , one on the Atlantic coast of Africa, 

 and three on the Atlantic coast of America; and three species 

 of dugongs (genus Dugong) on the shores of the Red Sea, Indian 

 Ocean, and Australia. 



Steller's sea-cow (Rhytina) formerly inhabited the north 

 Pacific, but became extinct about 1768 because its fearlessness 

 enabled hunters to kill it 

 easily. Sea-cows differ con- 

 siderably in structure from 

 whales. Their bones are 

 heavy, enabling them to 

 remain on the bottom; the 

 teeth are broad and crush- 

 ing; the lips are large and 

 movable and are used to seize seaweeds and other water-plants 

 upon which they feed ; the fore limbs are flexible flippers ; 



2X 



Fig. 541. — The American manatee, 

 Manalus lalirostris. (From Flower and 

 Lydekker.) 



