The Mammals 



2 — Those whose body forms are only partially developed within 

 the body of the mother and then removed to a pouch on 

 the underside of the body. In this pouch the young are 

 suckled until they are able to gather their own food. The 

 opossum and kangaroo belong to this order. The opossum 

 is the lowest order of mammals found in the United States. 



3 — Those that are hatched from an egg and suckled from the 

 breasts of the mother. 



This third group is the lowest order of the mammal 

 class. In Australia, "The Land of Inverted Orders," we 

 find living along the rivers an animal which the scientists call 

 Ornithorhynchus, a duck mole, which has the bill of a duck, 

 a body and tail resembling an otter and which lays one egg 

 each year from which its young is hatched. It then suckles 

 its young in the same manner as do the other mammals. The 

 duck moles and a type of ant-eaters are the only mammals 

 which lay eggs. 



The first of these groups may be divided into the follow- 

 ing orders : 



1 — Insect Eaters — such as moles and shrews. 



2 — Toothless Mammals — such as the anteaters, sloths and arma- 

 dillos. 



3 — Bats — insect eating flying mammals. 



4 — Rodents or Gnawers — such as mice, rats, squirrels and por- 

 cupines. 



S — Hoofed Mammals — One-toed: horse. Two-toed: cow, sheep, 

 etc. Four-toed: hippopotamus. Five-toed: elephant. 



6 — Mammals that have left the land and returned to the sea; 

 whales, seals, etc. 



7 — Flesh Eaters — cats, dogs, wolves, etc. 



8 — Man-like mammals — such as lemurs, monkeys and man. 



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