absence I once more pull back the prey. Fresh emergence of the Wasp, who
puts things to rights and persists in going down again, still by herself,
however often I repeat the experiment. Yet it would be very easy for her to
put an end to my teasing: she would only have to descend straightway with
her game, instead of leaving it for a moment on her doorstep. But, faithful
to the usages of her race, she behaves as her ancestors behaved before her,
even though the ancient custom happen to be unprofitable. Like the Yellow-
winged Sphex, whom I have teased so often during her cellaring-operations,
she is a narrow conservative, learning nothing and forgetting nothing.

Let us leave her to do her work in peace. The Locust disappears underground
and the egg is laid upon the breast of the paralysed insect. That is all:
one carcase for each cell, no more. The entrance is stopped at last, first
with stones, which will prevent the trickling of the embankment into the
chamber; next with sweepings of dust, under which every vestige of the
subterranean house disappears. It is now done: the Tachytes will come here
no more. Other burrows will occupy her, distributed at the whim of her
vagabond humour.

A cell provisioned before my eyes on the 22nd of August, in one of the
walls in the harmas, contained the finished cocoon a week later. (The
harmas was the piece of enclosed waste land in which the author used to
study his insects in their natural state. Cf. "The Life of the Fly," by J.
Henri Fabre, translated by Alexander Teixeira de Mattos: chapter 1.--
Translator's Note.) I have not noted many examples of so rapid a
development. This cocoon recalls, in its shape and texture, that of the
Bembex-wasps. It is hard and mineralized, this is to say, the warp and woof
of silk are hidden by a thick encrustation of sand. This composite
structure seems to me characteristic of the family; at all events I find it
in the three species whose cocoons I know. If the Tachytes are nearly