LOCUSTS OF BENGAL, MADRAS, ASSAM, € BOMBAY. 129 
obsolescent. The young wings, too, now first appear. At first very small, they grow 
during the period of this stage—20 days. The contents of the wing-sprouts are at 
first liquid, and the young wings may be seen forming within the semi-transparency. 
When they are fully formed, the insect is of a dark brownish-grey colour, whilst on 
the prothorax and elsewhere may be distinguished the colouring of the next stage. 
“Tn its 6th and perfect stage the insect presents a brilliant appearance. The female 
is now 8 inches, and the male 25 inches, in whole length, from head to tips of wings 
which overlap the abdomen by °5 of an inch, and are rounded. On casting the slough 
the wings dry and unfold, and the body of the insect, at first soft and moist, gradually 
hardens in the sun. The antenne are °8 inch in length, and of a bright yellow colour ; 
the head is a brownish-yellow, and the eyes, finely striated, are of a deep chestnut. 
The prothorax is alternately banded with a bright yellow and a rich brown, parallel- 
wise to the body, and the legs are of an ochreish hue. Along the upper rim of the 
femur runs a deep brown stripe, and the knee-caps are of the same colour. The tibia, 
tarsus, and foot are a bright ochre, and the first is armed with 8 black-tipped spurs on 
the outside and 11 on the inside, while there area pair of spurs on each side of the 
ankle-joint and on each side of the foot. The outer wings, or wing cases, have the 
colours on the prothorax extended to them, and on the back they form a flat 
surface, tapering to the extremity. They are strongly veined and finely reticulated, 
and towards the extremities are irregularly brown marked. The inner wings, which 
are expansive, are hardly coloured. The abdomen is a light brown, darker along the 
ridge, and in the female there are four spiky processes at its extremity, the upper pair 
curling up and the lower pair downwards. In the male the lower pair is replaced by 
one spiky process, larger and stronger. 
“The locust now packs with its kindred, and they form the swarms which ravage 
the country. After a month or so they assume a red tinge, which gradually deepens 
and continues until their death, which takes place after the sexual function has been 
performed in May or June. The proportion of males to females appeared to me about 
1in6. 
“ The whole life of the insect, including the egg-period, is exactly one year.” 
Various methods were employed in the Bombay Presidency in 1882-83 to 
destroy the locusts, which were to a large extent kept 
under by the energetic measures taken against them. 
The Cyprus screen system! was found utterly inapplicable and had to be 
abandoned. ‘The search for eggs also was not found successful as a means of 
Remedclies. 
1 The Cyprus screen system consists in erecting a long line of screens, each two to three 
feet high, in front of an advancing swarm of young wingless locusts, pits being dug at inter- 
vals, close to the screens and at right angles to them, on the side towards the advancing 
swarm, the object being that the young locusts, on arriving at the screens, may turn to the 
right and left, and thus pour into the pits, where they can be destroyed. The chief adyan- 
tage of the screen system is, that it enables a series of pits, dug at intervals, to take the place 
of the continuous trench that would otherwise be necessary to catch the whole of a swarm. 
The material hitherto chiefly used for the screens has been cloth bound along the top with a 
strip of slippery oil-cloth, about four inches wide, to prevent the locusts climbing over, but 
smooth mat screens are likely to be cheaper for use in many parts of India. The pits are 
usually furnished with overhanging zinc edges to preyent the locusts escaping. 
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