2
THE ESSEX NATURALIST.
mentioned. They state that the male is rare, but the females
can be seen during August, running about amongst the heather
in sandy parts of the commons where they occur. These places
are the haunts of the Tiger-beetles, Cicindela campestris and C-
sylvatica, and it is the burrows containing the larvae of these
beetles that are the objects of Methoca's search. The vertical
cylindrical burrows run down to the depth of as much as seven
or eight inches into the sandy soil, and the larvae station them-
selves at the top, with the head and cephalothoracic shield level
with the surface of the ground. The mandibles are held widely-
open ready to seize on any insect that approaches within range
of the area to which the larva can extend its anterior segments,
while it remains anchored in the burrow by the extremity of its
body and the hooks on the dorsal hump on the fifth abdominal
segment.
The first object of the Methoca is to dodge these powerful jaws
and yet obtain entrance to the burrow. Details reported by the
different observers do not quite agree as to the method employed.
According to Adlerz (as translated by Champion) the Methoca
begins to manoeuvre round the snapping larva till it gets an
opportunity to slip on to the lid (i.e., the cephalothoracic shield
of the larva, at the top of the burrow) from the dorsal side.
Instantly the head or the front part of the thorax of the
Methoca is grasped by the sickle-shaped mandibles of the larva,
and as the latter raises its head in so doing the Methoca is given
the opportunity to sting the larva in the throat or between the
front coxae. The larva is at once paralysed and the Methoca
rests at the edge of the burrow till the poison works its full effect.
After a short time the Methoca pushes past the head of the now-
powerless larva down into the burrow. These operations are
followed by the repeated stinging of the ventral thoracic
segments.
The Champions could only say that Methoca managed to
dodge round somehow or other and get down the hole. By
observing the proceedings in burrows in sand in glass vessels
they were able to see the Methoca sting its victim several times
in the thorax, paralysing it almost completely, then depositing
a single egg on it. She then proceeded to fill up the burrow with
any movable material at hand. Extraordinary care was taken
to render the whole indistinguishable from the surrounding