In many respects the insects of this section adopt the same methods as the
solitary bees so far as the construction of their nests is concerned, but
the food brought home for their offspring is animal instead of vegetable.
In order to supply their larvae with "fresh meat" these little creatures,
when they have captured a suitable prey, sting it in such a way that it
becomes paralyzed, but does not die; after provisioning a cell with the
necessary number of these paralytics, the mother lays her egg on one of
them or amongst them, and closes up the cell. In consequence of this
wonderful maternal instinct, foresight, or whatever the faculty may be, the
larva when hatched finds fresh food ready for consumption. The various
species provision their nests with different kinds of foods, and some
appear to be most fastidious in their selection, and are said never to err
in choosing {19} species of some particular family, thereby displaying a
discernment worthy of any advanced entomologist. Some provision their cells
with beetles, some with grasshoppers, others with spiders, caterpillars,
plant lice, etc.
The strength possessed by the female fossor must be proportionately
enormous, as she can bring back to her burrow, after paralyzing them,
insects many times her own size. It is a most interesting sight to see the
excitement and flurry of the captor as it tries to drag along some huge
prey to its nest. I remember seeing one dragging along a good-sized
caterpillar, of a noctuid moth, over rather rough ground: the poor creature
had a difficult job; it had to go backwards itself, and pull the body of
the caterpillar, after it--its behaviour was very much like that of an ant
which has a large burden; at times it would loose its hold of it and try it
from some other quarter; however, by degrees, by pulling and tugging, the
prey was safely brought home, but the force expended must have been very
great. Many species, however, hunt insects of much smaller size than
themselves, and it is those which take a fancy to grasshoppers and {20}
caterpillars which seem to be the most doughty in deeds of force. One, a
very rare kind in this country, sets its affection especially on the honey
bee as a prey; the two insects are about equal in size, but the hive bee
must be a dangerous foe to attack, and one would have thought as likely to
sting its captor as its captor would be to sting it; also one would imagine
that a hive bee, unless thoroughly paralyzed, would be a dangerous subject
for a juvenile larva to commence making a meal upon! but whether the
venture ever turns out unsatisfactorily there are no data to show, so far
as I am aware. The larvae must vary very much in their tastes; one can
imagine that a nice juicy caterpillar, or even a good fat grasshopper, may
be appetizing and easily assimilated, but one can equally fancy that the
larvae, who wake up to find their food consisting of small hard beetles,
may feel more or less resentment against their parents' ideas of dainties
for the young! Still they seem to thrive on it, and come out eventually as
exact likenesses of their parents. A large number of the fossors inhabit
dry sandy wastes, such as the dunes along the sea coast at Deal, Lowestoft,
{21} etc.; many of these, when they leave their burrows, throw up some sand
over the hole so as completely to cover it; how these insects find the spot
again after a lengthy chase after spiders or other prey is a marvel; and
yet those who have observed carefully say that they come home from long
distances with unerring precision. No sense of which we have any knowledge,
however accentuated, seems to explain this. To be able to arrive back at a
home in an extensive arid sandy plain, where no outward sign indicates its
whereabouts, must surely require perception of a different nature from any
of those with which we are endowed. Some fossors are subject to the
depredations of cuckoos, just as the solitary bees are, but their cuckoos
are rarely of aculeate origin. The only ones which I have had any
opportunity of studying are the species which nest in bramble stems. The
cuckoos which associate with them are some of the smaller jewel flies and
_Ichneumons_: the habits of both these differ from those of the aculeate
cuckoos, the jewel flies devouring the larva of the aculeate and the
_Ichneumon_ laying its eggs in it. The fossors {22} [Illustration: FIG. 2.]
vary exceedingly in size, shape and colour. Our largest species are about
an inch long and our smallest about the eighth of an inch, nearly all
having the body where it joins the thorax constricted into a very narrow
waist; this is sometimes of considerable length. In one genus known to
entomologists by the name _Ammophila_ (fig. 2) or "lover of the sand", the
waist is practically the longest part of the body, so that looking at one
sideways as it flies along, one could almost be deceived into thinking that
there were two insects, one following the other (cf. pl. A, fig. 7). In
colour, there seem to be three dominant schemes: Black (cf. pl. B, fig.
17); black with a red band across the body (cf. pl. A, fig. 7); and black
banded with yellow, like a wasp (cf. pl. A, figs. 6 and 8, etc.) In some
the yellow bands may not be complete, and appear only as spots on each side
of the body segments, or the red band may be almost obliterated, or the
black species may {23} [Illustration: FIG. 3.] [Illustration: FIG. 4.] be
more or less variegated with yellow spots on the head and thorax, but as a
general rule all our species fall into one or other of these colour
schemes. The females of some of our sand frequenting species have beautiful
combs on their front feet, each joint of the tarsi having one or more long
spines on its external side (figs. 3 and 4). These are of importance to
them in their burrowing, as they enable them to move with one kick of their
front leg a considerable amount of the dry sand in which they make their
nests. Although sandy commons, etc., are the resort of many fossors, others
may be found burrowing in wood or in hard pathways or banks; in fact, like
most other insects, some of their members may be found almost anywhere.
* * * * *
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