4 L. W. SACKETT 



Little is known of the geological history. The ancestry of the 

 porcupine family has not been traced back farther than the 

 Pleistocene age ; hence, practically nothing is known of the 

 history of the group. Remains of a species (Hystrix venustus) 

 have been found in the Pliocene of Nebraska, but it is probably 

 more closely related to the Old World porcupine than to the 

 American genus. There are also a few Tertiary South American 

 genera, but nothing has been made out directly connecting them 

 with the Erethizon genus. 



Description. — The weight of the adult porcupine varies from 

 12 pounds to 25 pounds, possibly larger. In appearance they 

 are low, heavy-set with strong fore legs and stronger hind legs. 

 The tail, slightly prehensile, is very strong, covered on the 

 bottom with stiff bristles and on the top and lateral edges with 

 heavy, short quills. The body is roughly conical, enlarging 

 from the flattened nose to the very broad hips, making the 

 animal well adapted to its habits of creeping around through 

 the low undergrowth of the woods. In color they have great 

 ^•ariation, ranging from pure white to a very dark brown or 

 black. The brown and the black porcupines are very common, 

 while the pure albinos are comparatively rare. The upper part 

 of the body of the adult porcupine is covered with quills from 

 the eyes and forehead to the tip of the tail, while the under 

 part has soft, short fur which becomes coarser and longer on 

 the sides next to the quills. Along the neck and shoulders these 

 quills are longer, more flexible and very thickly set. On the 

 rear half of the body the quills are shorter, very much heavier 

 and not so numerous, leaving the skin well exposed .when the 

 quills are erect. 



Seasonal Habits. — In its habits of life, the porcupine is noc- 

 turnal and perennial. On the first point there is little dispute. 

 They usually come out an hour or so after dusk and are usually 

 back in the dens an hour or two before dawn, thus avoiding 

 both the daylight and the twilight enemies. In spite of their 

 nocturnal habits they may frequently be seen roving about in 

 the daytime for no apparent reason. The writer has made 

 numerous and somewhat continuous observations throughout 

 the winter months, however, to correct the error found in much 

 of the literature to the effect that porcupines hibernate. It is 



