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 zigzags, as caprice, or more 
probably instinct, suggests, and as the scarcity or abundance of the 
prey sought for determines. . 
But the principal passage, or high road—as I may call it—is very 
earefully 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, to be sunk no less than eighteen 
_ inches below the surface. 


Plan of Molehill. 
is’ 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 
4 
