LITTLE BEASTS OF FIELD AND WOOD 



any cavity inside at first, but hollowed out later. 

 This, however, would seem a very impracticable 

 way of working when the difficulty of disposing 

 of the material removed is considered ; but per- 

 haps they simply dig down from the top and add 

 whatever is removed to the exterior, for the upper 

 chamber is often close to the surface, with only 

 a shallow covering of material, which allows a 

 passage for the air and sometimes for the inhabi- 

 tants themselves. The chamber is usually less 

 than a foot in diameter, and lined with soft grass 

 and moss ; a passage extends from this chamber 

 downwards and to one side, to another larger 

 one, more or less filled with water, and from 

 here down to still another, below the bed of the 

 stream itself The last is formed merely by the 

 junction of several burrows, some of which extend 

 up into the bank, and others to the deepest part 

 of the channel. 



This is the commonest type of cabin that I 

 have examined. Some of the smaller ones have 



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