500 SPINES OF PORCUPINE CHAP. 
and even occurring in Europe. There are several species, of 
which the common Hystriaz cristata is the best known, and is the 
one which is to be found in Europe. 
The spines of the common form and of the others are solid in 
the middle of the body, but on the tail they are expanded into 
hollow quills, which make much rattling. They are as a rule 
black and white, the middle of the spine being banded with 
black. A great crest of coarse long hairs on the head is 
responsible for the scientific name of the well-known form. 
Fic. 245.—Common Porcupine. Hystrix cristata. xh. 
Sometimes in this genus, as in the Tree Porcupines of Brazil, the 
spines are orange or yellow; but it is said that the colour is soon 
lost in this country. As a matter of fact it is the easiest thing 
in the world to wash out with ordinary tap-water much of the 
yellow colour of the spines of the South American Sphingurus. 
The same may be the case with the pigment of the Old-World 
Poreupines. There are fourteen to fifteen dorsal vertebrae and 
four or five lumbars. The tail varies in length, but is shorter 
than the long tail of the arboreal New-World forms. It seems 
impossible when mentioning the Porcupine to escape from some 
observations about its alleged habit of shooting its quills. For 
some reason or other Buffon has got the credit of inventing, or at 
