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Characteristic South American Animals. — The Neo- 

 tropical or South American realm is the richest of all 

 in species, because of its isolation, its varied conditions, 

 and its past geological history. It contains more 

 than half of all the vertebrate families of the world, 

 and more than one-fourth of these families occnr no- 

 where else. The order of edentates is the most 

 characteristic one here. It was formerly represented 

 in this area by many huge forms, though the present 

 day survivals are small. Of these we have shown 

 the armadilla with his bony coat of mail, within 

 which he can roll himself in time of danger. At other 

 times he will be found burrowing in the sand hills 

 like a rabbit. Upon the shelf at the back are two of 

 the ant-eaters, with their long toothless snouts through 

 a small hole in the end of which they protrude their 

 sticky tongues after ants. Below them is the family 

 of sloths. Notice how their feet are adapted to a 

 life spent in constantly hanging to the under side of 

 a branch. The ancestors of these animals were 

 among the largest of known mammals. The South 

 American monkeys dirfer much from the Old World 

 types, as shown by the prehensile tailed monkeys and 

 the interesting little marmosets that go skipping about 

 the trees like squirrels. The camels have four rep- 

 resentatives on this side of the Atlantic, of which two 

 are shown here, the llama, which has long been of 



