MOTIONS OF INSECTS. 367 
and rounds its curious and regular cells. The house- 
cricket (4. domestica), which, on account of the softness 
of the mortar, delights in new-built houses, with the same 
organs, to make herself a covered-way from room to 
room, burrows and mines between the joints of the bricks 
and stones 2, 
But of all the burrowing tribes, none are so numerous 
as those of the order Hymenoptera. Wherever you see 
a bare bank, of a sunny exposure, you always find it full 
of the habitations of insects belonging to it ;—and besides 
this, every rail and old piece of timber is with the same 
view perforated by them. Bees; wasps; bee-wasps (Bem- 
bex); spider-wasps (Pompilus); fly-wasps (Mellinus, 
Cerceris, Crabro), with many others, excavate subterra- 
nean or ligneous habitations for their young. None is 
more remarkable in this respect than the sand-wasp 
(Ammophila, K.), or as it might be better named—since 
it always commits its eggs to caterpillars which it in- 
humes—the caterpillar-wasp. It digs its burrows, by 
scratching with its fore legs like a dog or a rabbit, di- 
spersing with its hind ones, which are particularly con- 
structed for that purpose, the sand so collected®. 
Since most of these burrows are designed for the recep- 
tion of the eggs of the burrowers, I shall next describe to 
you the manner in which one of the long-legged gnats, 
or crane-flies (Tipua variegata, L.)—a proceeding to 
which I was myself a witness—oviposits. Choosing a 
south bank bare of grass, she stood with her legs stretch- 
ed out on each side, and kept turning herself half round 
4a White, Nat. Hist. ii, 80. 72. 76. b Linn. Trans. iv. 200—- 
