PORCUPINES. 163 
name from the French porc-épin (spiny-pig), probably in allusion to their grunting 
pig-like cries. They are common to both the Old and New Worlds; although the 
representatives of the group found in the two hemispheres constitute two distinct 
subfamilies. 
Canadian The common Canadian porcupine (/rethizon dorsatus) belongs to 
Porcupine. a croup confined to America, all the members of which are arboreal 
in their habits, while most of them have prehensile tails. They are all characterised 
by the absence of a cleft in the upper lip, by the naked soles of the feet being 
covered by a number of tubercles, by the want of the first toe in the fore-foot, and 
the presence of only three teats in the female. Their molar teeth have complete 
roots; and the collar-bones are fully developed. . dorsatus differs from its allies 
in having a short and nonprehensile tail; and also in the presence of five toes in the 
hind-feet. It is a heavy and clumsily-built animal, with long brown hair, almost or 
completely concealing 
the short spines, which 
are white with brown- 
ish tips. The length of 
the creature is about 2 
feet, and its weight 
from 15 to 20 lbs. The 
limbs, neek, ears, and 
muzzle are short; the 
ears being almost con- SKELETON OF PORCUPINE. 
cealed by the long bristly 
hair at the sides of the head. The claws are very long and powerful; and the tail 
massive and almost four-sided in shape. The stout spines vary in length from less 
than one inch to more than four inches in different parts of the body; they cling 
loosely to the skin, and are thus easily detached, and as they are slightly barbed at 
the points they make their way completely through the flesh of any animal in which 
they may become fixed. As in other members of the family, the quills, when the 
animal is in repose, lie smoothly and are directed backwards; but under the influ- 
ence of excitement they can be erected by the aid of a sheet of muscle underlying 
the skin. The Canadian porcupine extends in the country from which it takes its 
name as far northwards as the limit of trees, while in the United States it extends 
on the eastern side as far south as Virginia, and on the western coast from Alaska 
to Arizona and New Mexico. Despite its heavy form and nonprehensile tail, it 
is an adept at climbing, and spends the greater part of its time among the 
branches of trees. Dr. Hart Merriam states that although largely nocturnal, 
these animals may at times be seen abroad during daylight. Their lair is 

usually made among the clefts of rocks, but sometimes in a hollow tree or heap 
of bushes. Even in the cold climate of the Adirondacks, this porcupine, although 
less active in winter, never hibernates. Dr. Merriam writes that when one of 
these animals “has selected and settled himself in a tree to his liking, he may not 
leave it, day or night, until he has denuded it of the whole of its foliage. I have 
seen many hemlocks thus completely stripped, not a green twig remaining, even 
on the smallest bough. It seems incredible that so large and clumsy an animal 
