190 WILD NEIGHBORS CHAP, 
World species. All the quills, which are in reality 
only modified hairs, and are hollow and rigid like 
the stems of feathers, point backwards and ordina- 
rily lie close to the body, but may be erected by 
the voluntary action of muscles underlying the 
skin. This done, their points stand out on every 
side, presenting a chevaux-defrise within which 
the animal squats as secure as one of the High- 
land squares at Waterloo. 
The self-inflating spiny globe-fishes and the 
hedgehog (not to speak of thorny invertebrates, 
such as the sea-urchins, murices, etc.) enjoy a simi- 
lar defence; but the porcupine’s armament is supe- 
rior to any of these, for it is offensive as well as 
defensive. 
It is a long-discredited fable, of course, that the 
porcupine shoots his spines at a tormentor, just as 
we no longer believe that it lays eggs or brings 
water in its quills to its young; but the seed of 
truth in the matter is the fact that the quills are so 
loosely attached to the flesh as to be readily de- 
tached, and in fact some: may be flirted out when 
the animal shakes himself vigorously — something 
he never does if he can avoid it. Moreover, each 
spine is needle-pointed, and minutely but strongly 
barbed, so that it sticks in whatever touches it, and 
is immediately withdrawn from the skin. Thus 
any animal that leaps upon or bites a porcupine 
finds its paws, shoulders, and mouth full of de- 
tached quills, which so divert its attention for some 
