ackwards, her enormous prey,
which dangles beneath her. She climbs now a vertical plane, now a slope,
according to the uneven surface of the stones. She crosses gaps where
she has to go belly uppermost, while the quarry swings to and fro in the
air. Nothing stops her; she keeps on climbing, to a height of six feet
or more, without selecting her path, without seeing her goal, since she
goes backwards. A lodge appears no doubt reconnoitred beforehand and
reached, despite the difficulties of an ascent which did not allow her
to see it. The Pompilus lays her prey on it. The silken tube which she
inspected so lovingly is only some eight inches distant. She goes to it,
examines it rapidly and returns to the Spider, whom she at length lowers
down the tube.

Shortly afterwards I see her come out again. She searches here and
there on the wall for a few scraps of mortar, two or three fairly large
pieces, which she carries to the tube, to close it up. The task is done.
She flies away.

Next day I inspect this strange burrow. The Spider is at the bottom of
the silken tube, isolated on every side, as though in a hammock. The
Wasp's egg is glued not to the ventral surface of the victim but to the
back, about the middle, near the beginning of the abdomen. It is white,
cylindrical and about a twelfth of an inch long. The few bits of mortar
which I saw carried have but very roughly blocked the silken chamber at
the end. Thus Pompilus apicalis lays her quarry and her eggs not in a
burrow of her own making, but in the Spider's actual house. Perhaps the
silken tube belongs to this very victim, which in that event provides
both board and lodging. What a shelter for the larva of this Pompilus:
the warm retreat and downy hammock of the Segestria!

Here then, already, we have two Spider-huntresses, the Ringed Pompilus
and P. apicalis, who, unversed in the miner's craft, establish their
offspring inexpensively in accidental chinks in the walls, or even in
the lair of the Spider on whom the larva feeds. In these cells, acquired
without exertion, they build only an attempt at a wall with a few
fragments of mortar. But we must beware of generalizing about this
expeditious method of establishment. Other Pompili are true diggers,
valiantly sinking a burrow in the soil, to a depth of a couple of
inches. These include the Eight-spotted Pompilus (P. octopunctatus,
PANZ.), with her black-and-yellow livery and her amber wings, a little
darker at the t