238 GNAWING ANIMALS 



found dead with Porcupine quills piercing their nostrils and 

 muzzles. Getting one's ' back up ' is an expressive term 

 often applied to human beings when labouring under great 

 irritation. When the Porcupine is in its normally placid 

 humour the quills lie smoothly along its back ; but when it 

 is attacked it erects its panoply of spines and runs backward 

 against its foe. The strangely clothed Rodent sheds its 

 quills periodically, and some of them are always more or 

 less loose ; and when they pierce an enemy's skin they 

 remain there. Casual observation would lead one to 

 suppose that such a weapon would not seriously injure a 

 leopard, and in reality if the quill were withdrawn the great 

 feline would think little of the wound. But try as it will the 

 animal cannot get rid of the dart, for it carries projections 

 which not only foil all efforts to remove it, but assist it to 

 work its way further and further into the tissues, until 

 inflammation sets in and the animal dies of hunger. As a 

 matter of fact one of the large carnivores is in little danger 

 of meeting with such a fate, for one stroke of the paw upon 

 the head would effectually dispose of the Porcupine, even 

 before it could roll itself up into a ball for protection. 



The Porcupine is a nocturnal animal living in a burrow, 

 which it excavates with its long and powerful claws, and 

 wherein it lies in winter in a torpid state. Roots are its 

 staple food. The animal is not so clumsy as its appearance 

 would seem to indicate. It is as quick on its feet as it is 

 sharp of eye ; and three or four natives armed with spears 

 can rarely despatch the animal without their bare legs 

 showing traces of its swift offensive movements. Dogs are 

 usually trained to hunt the Porcupine, and their concerted 

 movements speedily bring about its undoing. While the 

 baited Rodent is endeavouring to injure its foes on its 

 flanks and rear, one of the dogs will dart at its defenceless 

 head and disable it by a single bite. 



Unlike those of the Old, the New World Porcupines are 

 tree-climbers, various species of which range over the 

 greater part of America that lies between Mexico and 

 Paraguay. They usually possess a partly prehensile tail. 



The Urson or Canadian Porcupine (Erithizon dorsatus), 

 Plate XXV. Fig. 2, is the only species found so far North, 



