80 THE AMERICAN BEAVER. 



my plan to show how completely they occupy a given 

 district, as their numbers increase, as well ns the rela- 

 tions of their dams and other erections to each other, 

 I have explored the area covered by the map with 

 more thoroughness than any other, in order, as far as 

 possible, to exhibit all of their works within its limits. 

 Undoubtedly many of the lesser have escaped observa- 

 tion, but the principal and most important have been 

 found. There are within this area sixty-three beaver 

 dams, without reckoning the smallest, from those 

 which are fifty feet in length, and forming ponds cov- 

 ing a quarter of an acre of land, to those which are 

 three hundred and five hundred feet in length, with 

 ponds covering from twenty to sixty acres of land. 

 It also contains many acres of beaver meadows, many 

 lodges, burrows, and artificial canals. 



A dense forest overspreads the land, with the ex- 

 ception of the beaver meadows and the clearings 

 made near the mines. Upon the margins of the 

 principal streams the prevailing trees are the tam- 

 arack and the spruce; upon the first rising ground, 

 back of these, we find the white and yellow birch, 

 the soft and bird's-eye maple, the poplar and the ash ; 

 and upon the hills the sugar maple, the oak, and sev- 

 eral species of pine. Among the bushes are the wil- 

 low, the alder, and the cranberry. In this area, 

 therefore, are assembled all the elements tending to 

 form an inviting beaver district; namely, numerous 

 small rivulets flowing through hard wood lands, upon 

 the bark of the trees of which they depend chiefly 

 for subsistence; and shallow, sluggish rivers, suffi- 

 ciently narrow between their banks to be traversed 

 by dams, and having deciduous trees adjacent, ^and 



