day.

The _caterpillar_ is of a sea-green colour, with four yellow lines, two
along the back and one on each side; and is to be found, in June and July,
feeding on lucerne and other plants of the same natural order.

The _chrysalis_ is very similar to that of _Edusa_, green, with a yellow
stripe.

In this country, the _butterfly_ first appears in August; but on the
Continent it seems to be double-brooded, being found in May as well as in
August.

* * * * *

THE BLACK-VEINED OR HAWTHORN BUTTERFLY. (_Aporia Crataegi._)

(Plate IV. fig. 1.)

When on the wing, this species might easily be mistaken by the
inexperienced for the common Cabbage {78} White; and, by virtue of this
_incognito_, does in all probability often escape from the terrors of the
net, which would speedily entrap him, were his real character known to the
young hunter; for this butterfly is one of those called, in entomological
slang, "_a good thing_"--a term expressive neither of superior excellence
nor beauty, but meaning that the insect can't be met with everywhere, or
every day, and when seen is always to be caught.

A closer view, however, shows it to be very distinct from all the other
"Whites;" its _decided black veinings on a milk-white ground_, in
conjunction with its large size, being sufficient for its immediate
recognition.

The outline of the wings, as well as the play of the veining lines on their
surface, is extremely elegant. It will be observed, that instead of the
feathered fringe that surrounds the wings of most butterflies, they are
bordered in this species by a stout nervure, forming a sharp black outline,
and giving a peculiarly chaste finish.

The under side differs in no mentionable respect from the upper--a very
rare circumstance in this tribe. From being very sparingly coated with
scales, the wings are semi-transparent, differing much in this respect from
those of the Garden White butterflies.

The female generally has the veins of the fore wings of a browner tint than
in the males.

This butterfly is one of the very local species, though its food plants are
everywhere to be found, in more or less abundance. {79}

The following localities, among others, have been recorded as producing
it:--Herne Bay, and other parts of the Isle of Thanet, plentifully; near
Faversham, Kent; Horsham, Sussex; New Forest; Brington, in Huntingdonshire;
near Cardiff, South Wales, plentiful.

The caterpillar