MAMMALIA 293 



America are the rabbits, hares (Leporidce) ; squirrels, 

 prairie-dogs, woodchucks, chipmunks, ground-squirrels, 

 flying squirrels (Sciuridce) ', beavers (Castoridce)-, pocket- 

 gophers (Geomidce) ; rats, mice, voles, muskrats (Muridce) ; 

 and porcupines (Ccendidce). The beavers are unique 

 among rodents in possessing a flat scaly tail which they 

 use for swimming. The porcupine's quills are peculiar 

 structures, which are to be looked upon as highly modified 

 hairs. They must be touched to do injury and cannot 

 be shot out as is sometimes believed. Rats have recently 

 been the subject of special interest because of the discovery 

 that their fleas commonly carry bubonic plague. 



Order 8. Pholidota. The scaly ant eaters, or pan- 

 golins, are peculiar mammals inhabiting Africa and parts 

 of Asia. Their bodies are covered with flat scales and they 

 roll themselves up into balls when molested, like armadillos. 



Order 9. Primates. This order includes the lemurs, 

 monkeys, apes, and man. Its representatives are mostly 

 found in the warmer parts of the earth and usually live 

 in trees. They are well adapted to arboreal life, usually 

 possessing thumbs and great toes opposable to the other 

 digits so that the hands and feet are admirably fitted for 

 grasping. Most primates are somewhat social in their 

 habits and usually go about in small bands. One young 

 is usually born at a time and it is attended with great 

 care. 



The lemurs (Lemuridce) are dog-like arboreal animals, 

 mostly confined to the island of Madagascar. They usually 

 have a long non-prehensile tail ^and the toes bear both 

 claws and flattened nails. The marmosets (Halpalidce) 

 are found in Central and South America. Their great toes 

 bear flat nails but the others have claws; the tail and ears 

 are long; the thumb is not opposable to the other digits; 

 the brain is rather large; and the space between the nostrils 

 wide. The South American monkeys (Cebidce) have flat 

 nails on all the digits and can oppose both the thumb and 

 great toe; the tail is usually long and prehensile; and there 



