LIBRARY

ORTHOPTERA 91
The members of this family are among the best known insects and are
familiar to almost every savage or civilized person. As a matter of fact, grasshoppers
and locusts have always been an important item of the diet of all aboriginal
peoples and are still consumed in considerable quantities in many parts of
the world. The term grasshopper is now generally restricted to the common
nonmigratory forms while the name "locust" 1 is reserved for those migratory
wanderers which have proved so destructive throughout all time. In Biblical
times the Hebrews referred to these insects under nine different names, each of
which signified destruction. Every large land mass, excepting only the frigid
zones, has its particular kind or kinds of migratory locusts and the problems
arising from them. Many species of grasshoppers are also quite destructive.
Aside from their economic significance these insects are most interesting to
collect and study. As will be seen from ihe keys they are frequently referred to
as short-horned grasshoppers because the antenna; rarely attain half the length
of the body. The head is somewhat sunk into the prothorax and has, besides
the large compound eyes, three small ocelli. The prosternum in many species
has a short peg·like process between the coxre of the forelegs. The fore- and
middle legs are small as compared with the hind legs in which the femora are
greatly thickened and the tibire long and armed with two rows of spines. These
hind legs serve admirably as a means of ground locomotion and to take off in
flight. Both the tegmina and membranous wings are used in flight. The latter
are often brightly colored. In certain species the rubbing of the costal margins
of the wings against the thickened veins of the tegmina in flight produces a loud
startling crackling noise. A dull-gray species, with beautiful pale blue underwings,
Circotettix thalassinus Saussure, common in the high Sierras of California,
is called the firecracker grasshopper because of its sound-making abilities.
Some grasshoppers stridulate by rubbing a keel-like ridge, or rarely a
series of 80 or 90 small pegs, situated along the inner surface of the hind femora,
against a raised vein on the thickened basal areas of the radius of the tegmina.
They are thus able to produce characteristic noises often referred to as fiddling.
Even the young may be observed going through the motions of fiddling though
they have no wings across which to draw the rasping femora. An auditory organ,
consisting of a tympanum variously designed, usually occurs in both sexes
on either side of the abdomen under the bases of the folded wings.
These insects have a simple type of development. The female normally deposits
the eggs in the soil. She drills a hole with the tip of the abdomen as deep
as that elastic part of the body will permit and deposits from 20 to 100 elon·
gated eggs in a matrix of a cement-like secretion within the hole. Thus the egg
mass may often be removed in its entirety and is frequently referred to as an
egg sac, egg flask, and egg packet. As many as 20 egg masses may be deposited
by a single female. In the cooler temperate regions the eggs are laid only in late
summer and fall and constitute the only hibernating stage, but in the subtropi·
cal and tropical regions living forms may occur throughout the entire year and
J The term "locust" is also unfortunately applied to the 17·year clcada or harvest fly as
well as to certain American trees.