290 HABITS AND INSTINCTS OF ANIMALS. CHAP. X, 



join their united labours in erecting their separate 

 habitations and building their dams.* A more par- 

 ticular account of these dwellings will be found else- 

 where. The American musquash (Fiber Zibethicus 

 Cuv.), although far inferior in its social instincts to the 

 beaver,, must, nevertheless, be included in the same 

 list. Dr. Richardson informs ust, that these ingenious 

 and prolific animals join their labour in erecting, for 

 their mutual accommodation, a cone-shaped dwelling 

 or house, the chamber of which they take care to raise 

 sufficiently high above the level of the water to ob- 

 viate the effects of inundation. te The chosen spot 

 is generally amongst long grass, which is incorporated 

 with the walls of the house, from the mud being de- 

 posited amongst it ; but the animal does not appear to 

 make any kind of composition, or mortar, by tempering 

 the mud and grass together : there is, however, a dry 

 bed of grass deposited in the chamber. When ice 

 forms over the surface of the swamp, the musquash 

 shows an admirable instinct in perforating it, for the 

 purpose of making breathing holes ; and these holes 

 are again protected from the frost by a covering of 

 mud. This is their winter habitation ; but, with the 

 return of milder seasons, our little animal constructs a 

 summer residence : he excavates or burrows, in the 

 banks of the lake or morass near to his winter habita- 

 tion, several branched tunnels, many yards in extent ; 

 at the extremity of these which, probably, all termi- 

 nate ultimately in a point is a small chamber, and in 

 this the young are brought forth and nursed. When 

 its house is attacked in the autumn, the usual season 

 for hunting the poor creature, it retreats to these 

 passages ; but in the spring," observes Dr. Richardson, 

 " they are frozen up." J Before quitting these pre- 

 eminently social quadrupeds, it will be interesting to 

 notice that, in the circle of the order Glires, they 

 occupy a station perfectly analogous to that of the 



* North Zool. vol. i. p. 110. f Id. ibid. p. 117. 



I Id. ibid. p. 113. 



