's
nest in my hand, move it, put it down and take it up again without
the insect's raising any objection: it continues its work even when my
magnifying glass is placed over it.

One of these heroines has come to inspect a nest of the Chalicodoma of
the Walls, most of whose cells are occupied by the numerous cocoons of
a parasite, the Stelis. The contents of these cells, which have been
partially ripped up to satisfy my curiosity, are very much exposed to
view. The windfall appears to be appreciated, for I see the dwarf ferret
about from cell to cell for four days on end, see her choose her cocoon
and insert her awl in the most approved fashion. I thus learn that
sight, although an indispensable guide in searching, does not decide
upon the proper spot for the operation. Here is an insect exploring not
the stony exterior of the mason's dwelling, but the surface of cocoons
woven of silk. The explorer has never found herself placed in such
circumstances, nor has any of her race before her, every cocoon, under
normal conditions, being protected by a surrounding wall. No matter:
despite the profound difference in the surfaces, the insect does not
waver. Warned by a special sense, an undecipherable riddle to ourselves,
it knows that the object of its search lies hidden under this unfamiliar
casing. The sense of smell has already been shown to be out of the
question; that of sight is now eliminated in its turn.

That she should bore through the cocoons of the Stelis, a parasite of
the mason bee, does not surprise me at all: I know how indifferent my
bold visitor is to the nature of the victuals destined for her family. I
have noticed her presence in the homes of bees differing greatly in
size and habits: Anthophorae, Osmiae, Chalicodomae, Anthidia. The Stelis
exploited on my table is one victim more; and that is all. The interest
does not lie there. The interest lies in the maneuvers of the insect,
which I am able to follow under the most favorable conditions.

Bent sharply at right angles, like a couple of broken matches, the
antennae feel the cocoon with their tips alone. The terminal joint is
the home of this strange sense which discerns from afar what no eye
sees, no scent distinguishes and no ear hears. If the point explored be
found suitable, the insect hoists itself on tiptoe so as to give full
scope to the play of its mechanism; it brings the tip of the belly
a little forward; and the entire ovipositor--inoculating-ne