AORIBIIDiE. 
77 
wings are short or reduced, the tegmina reduced to lobes or only 
partially developed. In the majority the wings are large, hyaline and 
many-veined, folding under the tegmina ; they are frequently coloured 
at the base with red, yellow or black. The tegmina and wings in flight 
function as one. The abdomen is long, the segments distinct; it con¬ 
tracts and expands telescopically to a great extent in the female, in copu¬ 
lation being excessively retracted, in oviposition extremely elongated. 
The external genital organs are well marked; the principal features of 
the female are the upper and lower chitinous valves, which are used for 
digging, the anus being above, the genital aperture below. In the 
male, the genital aperture is on the upper surface of the usually conspi¬ 
cuous ventral shield, which often ends in a point. There is a small pair 
of cercion.theapex of the abdomen at each side of the anus. Males and 
females are frequently of different sizes and also of different colours. 
The anterior legs are short, fitted for slow walking and clinging ; the hind 
legs are conspicuous by the great development of the femur and tibia; 
the tibia bends back on to the femur, the apex of the former reaching 
the base of the latter and from this attitude the tibia kicks back, giving 
the impetus of the leaping motion. The tibia is outwardly set with thick 
spines. The femur may be specially modified to produce vibration 
when rubbed against the tegmen. The. inner face of the femur bears a 
row of knobs ; the femur is rubbed up and down against a projecting 
vein of the tegmen, causing the latter to vibrate. Under the tegmen, on 
the side of the basal abdominal segment, may be seen the auditory 
organ, visible as a round depression in the integument, and containing 
the tightly stretched tympanal membrane. Spiracles are situated on 
the thorax and on the membrane connecting the notum and sternum of 
the first eight abdominal segments. The tracheal system is character¬ 
ised by having bladder-like dilatations of some of the vessels, which are 
inflated previous to flight and while increasing the bulk of the insect, 
diminish its specific gravity and facilitate flight. 
The life history of the known Indian grasshoppers is uniform in the 
main outlines but only a small proportion have been worked out. Eggs 
are, so far as known, universally deposited in the soil in a compact 
cluster, with gummy matter which hardens and compacts the mass 
