The Sloe-Weevil 
chimney in the cone. I have indeed caught 
sight of a white, powdery speck at the top 
of the central cone. This tunnelled cone 
therefore is a lift which carries away the 
rubbish of the excavation. 
But the use of the curious building cannot 
be limited to this: the ever thrifty insect 
has not gone to the pains of building a tall, 
hollow obelisk with the sole object of 
preparing a thoroughfare for the atoms of 
dust that hamper the grub in its labours. 
The same result could be obtained with less 
trouble; and the Weevil is too sensible to 
construct the complex when the single would 
sufice. Let us look at things more closely. 
Evidently the egg, laid in a cup on the 
surface of the stone, needs a protecting roof. 
Moreover, the grub, which will presently be 
working at the bottom of its cup to reach 
the kernel, will require a refuse-shoot in its 
restricted quarters. A small, shallow dome, 
with a window to get rid of the sweepings, 
would, it seems, fulfil all the requisite 
conditions. Then why the luxury of this 
pyramidal chimney which rises to the top- 
most level of the pit, as a cone in eruption 
rises in the centre of a volcanic crater? 
215 
