134 Cockroaches, Locusts, Grasshoppers, and Crickets 
will move slowly on, walking and hopping for many miles, eating every 
green weed and grass-blade in their path, but this is only a limited and 
local sort of migration. 
Almost all the Acridiidae, despite the many species in the family, are 
readily recognizable as locusts 
or grasshoppers — short-horned 
grasshoppers they may be called, 
to distinguish them from the 
meadow green grasshoppers with 
long thread-like antennae—because 
of their general similarity in ap¬ 
pearance and habit. The body 
is rather robust, the head is set 
with its long axis at right angles 
Fig. 165.—Locust from lateral aspect (left wings 
removed), showing ( ao .) auditory organ. 
(Natural size.) 
with the axis of the body, so that the mouth with its strong biting and 
crushing jaws is directed downwards (Fig. 165); the antennae are never 
as long as the body and are composed of not more than twenty-five 
segments; the pro thorax is covered laterally as well as dorsally by its large 
saddle-like horny pronotum, which projects so as also to cover and protect 
from the sharp grass-blades the soft thin-walled neck and the equally 
thin-walled suture between prothorax and mesothorax; the abdomen is 
broadly and closely joined to the metathorax, and 
in the female ends in a short and strong ovipositor 
composed of four horny pointed pieces; the hind 
legs are much larger than the others and fitted 
for leaping, and the fore wings, called tegmina, 
are narrow and straight-margined, and serve 
specially to cover and protect the much larger 
thin membranous hind wings, which are plaited 
and folded like a fan when the locust is at rest. 
The sounds or stridulation of locusts are 
made in two ways. When at rest certain species 
draw the hind legs up and down across the wing- 
covers so that numerous fine little ridges on the 
inner surface of the broad femora are rasped Fl0 . l66 ._ Locus t impaled on 
across a thickened and ridged longitudinal vein thorn by shrike (butcher- 
on the outer surface of the wing-covers. When bird )* (Natural size.) 
in flight certain locusts rub or strike together the upper surface of the 
front edge of the hind wings and the under surface of the fore wings 
or tegmina. This produces a loud, sharp clacking which can be heard 
for a distance of several rods. The loudest “clacking” of this kind 
