By the Rev. A. C. Smith. 



313 



has been thoroughly searched; they are also oftentimes of very 

 intricate pattern, carried on in a series of zig-zags, as caprice, or more 

 probably instinct, suggests, and as the scarcity or abundance of the 

 prey soug'ht for determines. 



But the principal passage, or high road — as I may call it — is very 

 carefully constructed, with a view, not only to ready access to all 

 parts of the domain, but to security and escape by flight from 

 the enemies which sometimes pursue it home, the weasel and the 

 rat. This main passage moreover is thought to be generally formed 

 by the consolidation or " compression of the earth which surrounds 

 it, rather than by actual excavation ; and hence the infrequency of 

 mole-hills over it, compared with the number which are observed in 

 connection with the lesser galleries or alleys, in forming which the 

 earth is removed out of the way by being thrown up on the surface/' 

 This principal highway, into which all the other passages open, ex- 

 tends from the fortress to the extreme limit of the ground occupied : 

 it varies in depth, according to the looseness or firmness of the soil 

 in which it is constructed, and its consequent security from injury 

 by pressure from above ; and whereas it has sometimes been found at 

 a depth of only four or five inches, in other cases it has been known, 

 when circumstances required it, tc be sunk no less than eighteen 

 inches below the surface. 



Plan of Molehill. 



And now let me draw attention to the illustration, which I have 

 taken from a German book on zoology, and which is at once the 

 most simple and the most accurate sketch I have seen. The plan 



