been written upon the subject, there are things which we
do not yet know about this insect or its habits. We do not know what
precise influences cause their migration, nor do we know what is the
exact length of life of the locust or its breeding power, or the precise
locality in any country which may be defined as its permanent abode.
Locusts are classified under the order of orthopterous insects of the
family Acrydiidae, and are very closely related to grasshoppers.

There are a large number of species, the differentiating features being
more or less the form and sculpture of protorax, the size of the head,
the length and size of the prosternal spine, the comparative length and
size of the hind thighs and shanks, the amount and arrangement of the
tegmina mottlings, the comparative length of wings, and the general
build of the entire insect, which may be robust or fairly slender.

A general description of the distinctive physical features of migratory
locusts might be given as a strong, wild-looking head, a strong collar
inside which the neck moves, powerful and peculiarly-formed legs
attached to a short, strong, square trunk or thorax, four wings, two
antennae or feelers, six legs, and a long segmentary abdomen. The ground
colour of the locust is generally brownish, straw, or red, but its
colour varies somewhat according to the particular season of the year
or some other peculiar circumstance, but nothing certain is known as to
what influences the shade of colour. Mere ground colour is immaterial
and does not signify a new species.

Besides having a pair of compound eyes which form so noticeable a
feature in its head, there are three other simple little eyes, placed
like shining dots at three angles of a triangle below the two feelers.

The mouth, which is a fearful apparatus, consists of nine distinct and
well-marked organs; an interior or upper lip, consisting of a plate
deeply cleft and capable of opening enormously; two true jaws or
powerful mandibles; and two pairs of jointed organs called (maxillary)
palpi, and two lower jaws. The mandibles and jaws move laterally from
right to left.

The thorax or trunk consists really of three rings. To the first is
attached the two front legs; to the second, the two middle legs and the
first pair of wings, and to the third, the two hind legs and the second
pair of posterior wings. Along the posterior margin is a well marked
serrated (spinous) arrangement by means of which