6 L. W. SACKETT 



Habitat and Feeding. — The dens of the porcupine are in the 

 crevices of ro(?ky ledges. It is impossible to observe them in 

 the dens, but if one may judge from the habits of animals in 

 captivity, they select their accustomed cranny, and their own 

 private corner of that, roll up in a manner peculiar to the species, 

 appearing almost spherical, with the weight of their body on 

 the hind feet and tail, chiefly on the tail, with the fore arms 

 dropped between the arched knees, and with the nose nestling 

 between the fore paws. In this position they sleep throughout 

 the day with scarcely a movement, except such as any sleeping 

 animal. W'ill make to relieve strain and promote circulation. In 

 districts where denning is less favorable they si:>end most of 

 their time in the trees, feeding at night and remaining in the 

 hollow trees or rolled up on a limb during the day; hence, the 

 German name " Bamustachelschwein," or " Kletterstachelschwein." 



Their natural food consists chiefly of the soft inner bark, 

 leaves, twigs, etc., of trees. They feed chiefly on poplar, hem- 

 lock, fir, juniper and slippery elm. Early in the fall it is the 

 custom of the porcupines to limit their feeding grounds to some 

 specific cluster of trees. This results in the beating down of 

 regular paths between the feeding grounds and the dens. For 

 example, on September 2nd there was but one trail leading from 

 a certain well colonized den which the writer had under obser- 

 vation. Two weeks later there were four of these paths. Soon 

 after, a new one was marked out and all showed the results of 

 regular use. Throughout the following winter, the animals 

 followed these trails, approximating them even through the 

 deepest snows. When spring came they abandoned the trails 

 and fed again promiscuously over the forest with no definite 

 routes for leaving the dens or returning to them. 



In captivity they eat vegetables of most kinds but prefer 

 cabbage, carrots and, most of all, sweet potatoes. Several animals 

 learned to eat corn bread and refused all other kinds of food 

 when that was obtainable. They would usually eat one kind 

 of food for weeks or even months at a time, a fact, no doubt, 

 bearing some relation to the tendency of the animal to return 

 so persistently to the same group of trees for feeding in the wild. 



Viability, Reproduction and Development. — The age, or span of 

 life of the porcupine is not known ; but from slowness of repro- 



