e
test-tube with another tube, the width of the neck of a claret bottle.
The mouth is closed either with wire gauze, or with a paper cover with a
slight cut in it. Altogether, the apparatus measures twenty-five inches
in height. No matter: the fall is not serious for the lithe backs of the
young grubs; and, in a few days, the test-tube is filled with larvae,
in which it is easy to recognize the flesh fly's family by the fringed
coronet that opens and shuts at the maggot's stern like the petals of
a little flower. I did not see the mother operating: I was not there at
the time; but there is no doubt possible of her coming nor of the great
dive taken by the family: the contents of the test-tube furnish me with
a duly authenticated certificate.

I admire the leap and, to obtain one better still, I replace the tube
by another, so that the apparatus now stands forty-six inches high. The
column is erected at a spot frequented by flies, in a dim light. Its
mouth, closed with a wire gauze cover, reaches the level of various
other appliances, test-tubes and jars, which are already stocked or
awaiting their colony of vermin. When the position is well known to the
flies, I remove the other tubes and leave the column, lest the visitors
should turn aside to easier ground.

From time to time, the bluebottle and the flesh fly perch on the
trellis-work, make a short investigation and then decamp. Throughout the
summer season, for three whole months, the apparatus remains where it
is, without the least result: never a worm. What is the reason? Does
the stench of the meat not spread, coming from that depth? Certainly it
spreads: it is unmistakable to my dulled nostrils and still more so to
the nostrils of my children, whom I call to bear witness. Then why does
the flesh fly, who but now was dropping her grubs from a goodly height,
refuse to let them fall from the top of a column twice as high? Does
she fear lest her worms should be bruised by an excessive drop? There
is nothing about her to point to anxiety aroused by the length of the
shaft. I never see her explore the tube or take its size. She stands on
the trellised orifice; and there the matter ends. Can she be apprised
of the depth of the chasm by the comparative faintness of the offensive
odors that arise from it? Can the sense of smell measure the distance
and judge whether it be acceptable or not? Perhaps.

The fact remains that, despite the attraction of the scent, the flesh