446 
DISCURSIVE NOTES ON THE 
spider, grasshopper, or cricket, it is much too heavy to be 
carried in flight, and the Fossor then walks with it in her 
mandibles, carrying it up hill and down dale, over rocks with 
perpendicular faces, through all kinds of difficulties until, 
somehow or other, the toiler arrives back at the burrow. Some- 
times the prey is too heavy even to be carried by walking, and 
requires to be dragged along : a tedious performance, so that 
the shorter the distance the better. In these cases the general 
rule seems to be that the Fossor first finds the prey, and then 
digs a burrow for it in the nearest suitable locality. 
On one occasion, I was watching a Sphegid (Ammophila 
beninensis), which I found at the stage when she had arrived 
with her prey — a large Noctuid caterpillar — at the mouth of 
the burrow. The next step is always the same : the caterpillar, 
which lies helpless in a slightly curved attitude, is put down 
at the brink of the hole, with the head at the very edge. The 
Sphegid then goes down backwards, and at the last moment 
seizes the caterpillar with her mandibles, just behind its head, 
and drags it down to the chamber at the bottom of the burrow 
where there is room for both. There the caterpillar is bestowed, 
the Sphegid lays her elongated white egg upon its side at about 
the middle of the body, and, having climbed out, proceeds to 
fill up the burrow. 
In this particular case, however, the caterpillar was so 
much too large for the chamber that the Ammophila could 
only just squeeze her way up the passage into which its tail 
projected — almost up to the surface. This would not do at 
all, and the chamber had to be enlarged ; in order to do this 
it was first necessary to extricate the caterpillar from the 
burrow — a difficult job. However, she managed it. Standing 
over the mouth of the burrow, the Ammophila reached down 
and grasped the tail end of the caterpillar with her mandibles 
as far forward as she could reach, pulled it up and held it 
between her forelegs while she shifted her mandibles farther 
forward, and thus by repeated manoeuvres was able to draw 
out the over-sized caterpillar. Down she went and enlarged the 
chamber with ‘ tooth and nail,’ bringing out several 4 armfuls ’ 
of earth, and depositing them, with a little buzz as of protest, 
a few inches away from the hole. Then she went in again, 
