ORDERS OF MAMMALIA. 293 



catch by protruding their long and sticky tongues, having 

 previously broken into the nests by means of their strong, 

 curved claws. 



The Edentata are represented in the Old World by only 

 two genera. One of these is the genus Manis, comprising 

 the scaly Ant-eaters or Pangolins, which are exclusively con- 

 fined to Asia and Africa. In these singular animals the body 

 and tail are covered by a flexible armor, composed of horny 

 plates or scales overlapping like the tiles «f a roof. The 

 other genus is Orycteropus, comprising only the so-called 

 Ground-hog of South Africa ; which also lives upon insects, 

 and burrows by means of its strong digging-claws. 



As regards the geographical distribution of the Edentata, 

 it is to be remembered that the order has a very limited range 

 at the present day. The true Ant-eaters, the Armadillos, 

 and the Sloths, are exclusively confined to South America, in 

 which country a group of gigantic extinct Edentates existed 

 in the later portion of the Tertiary epoch. The scaly Ant- 

 eater is common to Asia and Africa; and the Ground-hog is 

 confined to South Africa. 



Oedek rV. SiEENiA (Gr. seiren, a Mermaid). — This order 

 comprises only certain large marine Mammals, known as Du- 

 gongs and Manatees, which were long classed with the Whales 

 and Dolphins ( Cetacea). They agree with the Whales in the 

 adaptation of the body to an aquatic Ufe, especially in the 

 facts that the anterior limbs are converted into swimming- 

 paddles, the hind-limbs are wholly wanting, and the hinder 

 end of the body forms a powerful caudal fin, which is placed 

 so as to strike the water horizontally, and not vertically as in 

 Fishes. They difiier from the Cetacea in having the nostrils 

 placed at the anterior part of the head, and in having molar 

 teeth with flat crowns, adapted for a vegetable diet. Fleshy 

 lips are present, the upper one usually with a mustache, and 

 the skin is covered with scanty bristles. The head is not dis- 

 proportionately large as compared with the body, and there is 

 a tolerably distinct neck. They are vegetable-eaters, feeding 

 chiefly upon sea-weeds, and haunting the mouths of rivers and 

 estuaries. 



The only existing Sirenia are the Manatee (Manatus) and 

 the Dugong [Halicore), often called " Sea-cows." The Man- 

 atees are found on the east coast of America, and on the west 

 coast of Africa. They are large, awkward animals, attaining 

 a length of from eight to ten or fifteen feet, and their flesh is 



