SCAI.Ol'S AOUATICUS. I 55 



excavate a gallery several hundred yards in length ; and I have 

 myself traced a fresh one nearly one hundred yards. The only 

 method by which we can arrive at a just appreciation of the magni- 

 tude of this labor is by comparison ; and computation shows that in 

 order to perform equivalent work a man would have to excavate, in 

 a single night, a tunnel thirty-seven miles long, and of sufficient size 

 to easily admit of the passage of his body. 



In following the galleries of the Shrew Mole one finds a number 

 of little hills of loose earth, each measuring from four to six inches in 



O 



height, and eight to ten in diameter. They are usually in groups, 

 a few feet apart, but are sometimes isolated. Lawns and flower beds 

 are often disfigured by them in a few hours, for a large number are 

 sometimes thrown up in a surprisingly short space of time. " I have 

 often examined these eminences," writes Dr. Godman, " and have 

 never been able fully to understand how they are formed ; a slight 

 motion is observed at the surface, and presently this loose earth is 

 seen to be worked up through a small orifice, whence, falling on all 

 sides, by its accumulation the hills just mentioned are produced. It 

 seems to be brought from some distance, for on breaking up the 

 gallery, it was evident that more earth had been thrown out than 

 could have been removed in excavating the immediately adjoining 

 portions of the burrow. In one instance I have seen the shrew-mole 

 show the extremity of its snout from the centre of one of these loose 

 hills, where it had come at mid-day, as if for the purpose of enjoying 

 the sunshine, without exposing its body to the full influence of the 

 external air." * 



I have many times observed small areas, several square yards in 

 extent, particularly in meadow-land, where the ground was fairly 

 covered with mole-hills, and so cut up with their galleries that in 

 walking over it one was sure to break through the surface. It seems 

 reasonable to suppose that the animal discovers, in these places, an 



* Loc. cit., p. 62. 

 I I 



