ments are made in the enclosure of a bell-cage, one
might imagine that captivity impels the flock to feed, in the absence
of better things, on what it would refuse were it free to hunt for
itself. Having naught else within their reach, the starvelings consume
any and all Cruciferae, without distinction of species. Can things
sometimes be the same in the open fields, where I play none of my
tricks? Can the family of the White Butterfly be settled on other
Crucifers than the cabbage? I start a quest along the paths near the
gardens and end by finding on wild radish and white mustard colonies as
crowded and prosperous as those established on cabbage.

Now, except when the metamorphosis is at hand, the caterpillar of the
White Butterfly never travels: he does all his growing on the identical
plant whereon he saw the light. The caterpillars observed on the wild
radish, as well as other households, are not, therefore, emigrants who
have come as a matter of fancy from some cabbage-patch in the
neighbourhood: they have hatched on the very leaves where I find them.
Hence I arrive at this conclusion: the White Butterfly, who is fitful
in her flight, chooses cabbage first, to dab her eggs upon, and
different Cruciferae next, varying greatly in appearance.

How does the Pieris manage to know her way about her botanical domain?
We have seen the Larini (A species of Weevils found on
thistle-heads.--Translator's Note.), those explorers of fleshy
receptacles with an artichoke flavour, astonish us with their knowledge
of the flora of the thistle tribe; but their lore might, at a pinch, be
explained by the method followed at the moment of housing the egg. With
their rostrum, they prepare niches and dig out basins in the receptacle
exploited and consequently they taste the thing a little before
entrusting their eggs to it. On the other hand, the Butterfly, a
nectar-drinker, makes not the least enquiry into the savoury qualities
of the leafage; at most dipping her proboscis into the flowers, she
abstracts a mouthful of syrup. This means of investigation, moreover,
would be of no use to her, for the plant selected for the establishing
of her family is, for the most part, not yet in flower. The mother
flits for a moment around the plant; and that swift examination is
enough: the emission of eggs takes place if the provender be found
suitable.

The botanist, to recognize a crucifer, requires the indication provided
by the flower. Here the