ERETHIZON DORSATUS. 
205 
His familiarity at such times is surprising, for, while not aggres- 
sive, he is by no means timorous, and explores the camp with cool- 
ness and determination. 
Porcupines have a curious habit of girdling trees, at a height of 
from six to thirty feet. The zone from which the bark is removed 
varies from a few inches to a foot or more in breadth. The spruce 
is more frequently girdled than any other tree, and those of small 
diameter more commonly than those of large size. 
When feeding on lily-pads along the borders of water-courses 
they sometimes utter extraordinary noises, and occasionally quar- 
rels arise for the possession of some log which affords them easy 
access to the coveted plants. At Beaver Lake, in Lewis County, 
Mr. John Constable once witnessed an encounter during which one 
of the combatants was tumbled into the water. The animals did 
not attempt to bite, but growled and snarled and pushed. 
Mr. Eugene P. Bicknell, while encamped on the summit of Slide 
Mountain in the Catskills, in June, 1882, was favored by a visit 
from a number of these curious animals, and his account of their 
actions well illustrates some of their prominent characteristics. 
Mr. Bicknell says : “ From evening till morning dusk our cabin on 
the extreme summit of the mountain was virtually besieged by 
them, and through the chinks their dark forms could be seen mov- 
ing about among the shadows in the moonlight, while their sharp 
cries, and often low conversational chatter, singularly like the 
voices of infants, were weird interruptions of the midnight silence, 
or later, of the moaning wind. 
“ The seeming nocturnal temerity of these creatures appeared to 
be simply an exhibition of excessive stupidity. It was found 
impossible to drive them from the camp for any length of time ; 
they seemed to be destitute of the faculty of memory, and even a 
light charge of shot sent among them was only for the moment 
effectual. Even when one particularly stupid individual had been 
shot dead in the doorway trying to effect an entrance by gnawing 
