AFRICAN GNAWERS 261 



but few which .are furnished with so singular a structure as the well- 

 known porcupine, whose wonderful array of spear-like quills has earned 

 for it world-wide renown. But for this prickly coat the porcupine 

 would have no chance of beating ofif its foes, for it is neither a strong 

 nor a swift animal, and so would be unable either to fight with or to 

 escape from an antagonist larger than itself. 



There is one very great mistake, however, which people often 

 make with regard to this curious spiny covering, and that is to sup- 

 pose that the porcupine can use its quills in the manner of spears, 

 and hurl them at any foe who is foolish enough to come within dis- 

 tance. This power, however, the animal does not possess. All that 

 it can do when attacked is to spread its quills and run backwards 

 towards its foe, for it is quite unable even to loosen its spines in their 

 sockets, much less to hurl them through the air and so strike its 

 enemy at a distance. It is true enough that animals are sometimes 

 found with one or more quills piercing their bodies, but these are such 

 as have attacked a porcupine and have borne away with them 

 evident signs of the encounter. For the quills of the porcupine are 

 set quite loosely in the skin, and are furnished with saw-like edges, so 

 that, when they enter the flesh of an animal, they not only remain in 

 the wounds, but constantly penetrate deeper and deeper. Even so 

 powerful an animal as the tiger has been found to have his head and 

 paws filled with the spines of a porcupine, which he had attacked, but 

 had failed to conquer. 



These terrible spines are nothing more nor less than hair. If 

 one is split up very carefully, it is found that it is formed of a number 

 of hair-like threads j^ressed very closely together, and these threads if 

 placed under a microscope, would be found to possess just the same 

 structure as real hair. The same is the case with the horn of the 

 rhinoceros, which, verv different though it appears, is really formed of 

 nothing more than hair. 



