Mammalia. 259 



skull is therefore well protected, so that it may receive a 

 severe mauling and not be much the worse, except for 

 external bruises. The opossum is of a low order of intelli- 

 gence, and appears stupid, both when free and in confine- 

 ment. It has not sense enough to become a pet. 



The kangaroo is another well-known marsupial. The 

 story of its development is about the same as that of the 

 opossum, but the mode of life is different. The hind legs 

 are excessively developed, and the animal hops with 

 " record-breaking " power, seldom putting the feeble fore 

 legs to the ground. When standing, the strong, muscular 

 tail aids in supporting the body, forming a third leg, so to 

 speak. The kangaroo is entirely herbivorous. There are 

 many other marsupials in Australia, and, in fact, with the 

 exception of the opossums, all the living marsupials are 

 confined to the Australian region. Many countries yield 

 fossil remains of marsupials, some of large size, showing 

 that Australia contains the remnants of this peculiar, but 

 once widely distributed race. It is further interesting to 

 note that Australia has no other native mammals than the 

 marsupials, except possibly the dingo, or wild dog, which 

 some believe to have been introduced. 



PLACENTAL MAMMALS. 



All the mammals above the marsupials are born in a 

 more mature condition. 



The Edentates. This order includes the sloths, arma- 

 dillos, etc. They are not wholly toothless, as the name 

 would indicate, but the teeth, when present, are simple or 

 imperfect. They are mostly tropical, one armadillo occur- 

 ring in southwestern Texas. 



The sloths are herbivorous and tree-inhabiting. They 

 climb, hanging under limbs by their hooked claws, and as 



