able, turning one end towards the full light of a sunny window,
the captives at once make for the brighter end and play about there for
a long while, without seeking to retreat. If I turn the tube in the
opposite direction, the crowd immediately shifts its quarters and
collects at the other end. The brilliant sunlight is its great joy.
With this bait, I can send it whithersoever I please.

We will therefore place the new receptacle, jar or test-tube, on the
table, pointing the closed end towards the window. At its mouth, we
open one of the full tubes. No other precaution is needed: even though
the mouth leaves a large interval free, the swarm hastens into the
lighted chamber. All that remains to be done is to close the apparatus
before moving it. The observer is now in control of the multitude,
without appreciable losses, and is able to question it at will.

We will begin by asking:

"How do you manage to lodge your germs inside the caterpillar?"

This question and others of the same category, which ought to take
precedence of everything else, are generally neglected by the impaler
of insects, who cares more for the niceties of nomenclature than for
glorious realities. He classifies his subjects, dividing them into
regiments with barbarous labels, a work which seems to him the highest
expression of entomological science. Names, nothing but names: the rest
hardly counts. The persecutor of the Pieris used to be called
Microgaster, that is to say, little belly: to-day she is called
Apanteles, that is to say, the incomplete. What a fine step forward! We
now know all about it!

Can our friend at least tell us how "the Little Belly" or "the
Incomplete" gets into the caterpillar? Not a bit of it! A book which,
judging by its recent date, should be the faithful echo of our actual
knowledge, informs us that the Microgaster inserts her eggs direct into
the caterpillar's body. It goes on to say that the parasitic vermin
inhabit the chrysalis, whence they make their way out by perforating
the stout horny wrapper. Hundreds of times have I witnessed the exodus
of the grubs ripe for weaving their cocoons; and the exit has always
been made through the skin of the caterpillar and never through the
armour of the chrysalis. The fact that its mouth is a mere clinging
pore, deprived of any offensive weapon, would even lead me to believe
that the grub is incapable of perforating the chrysalid's covering.

This proved error makes me dou