458 
DISCURSIVE NOTES ON THE 
over the back, and the noise made by Sceliphron may be 
analogous. 
This singing at work seems to be the prerogative of the 
Sphegidce. I cannot, for the moment, remember that the 
Pomjpilidce ever do it, and Bernbex certainly does not. Often, 
if you observe with your ears, as a field naturalist should do, 
and not only with your eyes, your attention will be attracted 
by an intermittent buzzing which, as you trace it to its source, 
seems to come from under the ground. Approach gradually, 
and you will see a small round hole with freshly excavated 
earth at its mouth. Suddenly, a long, thin-bodied insect 
backs out of the hole, bearing between her fore-limbs an 
4 armful ’ of earth, which she puts down a few inches away — • 
often with a little buzz, as if of satisfaction. She again launches 
herself into the hole with headlong vigour, and a loud buzzing 
attests her efforts to loosen the firm soil. 
If you have watched one from the commencement of 
digging the burrow, you will see that she endeavours to scrape 
out an 4 armful ’ of earth with her powerful fore-limbs ; but if it 
is too hard, or she meets with a small pebble in the way, she 
has to bite it out, and this always produces a sort of protesting 
buzz at being so hampered in the work; for these Eossors 
seem to work at very high pressure, and as if on springs, 
antennae vibrating and wings flicking with superabundant 
energy. Finally, the chamber at the bottom of the burrow, 
several inches underground, is completed, and all is ready 
for the prey. If the accustomed prey is of large size it has 
been first found and stung, and the burrow excavated close 
to where it lay. If the Fossor is one that chooses prey which 
she can carry, the burrow is first made, the prey then sought 
out and brought back. 
Having satisfied herself that the home is ready, the Sphegid 
pays particular attention to concealing the entrance before 
she goes away. A few small bits of stone are picked up in 
her mandibles and securely wedged in the entrance, and she 
then stands with her head away from the spot and scratches 
fine earth backwards so as to conceal completely the mouth of 
the burrow. Finally, after very careful examination, she flies 
off, and then you may see her quartering the ground for the 
