RICE HISPA. 115 



egg hatches to a small, flattened grub, with three pairs of legs, which lives 

 inside the leaf between the upper and lower epidermis. The gnib is white or 

 3'ollow with black markings, very flattened, the first three segments broader 

 than the abdomen. It feeds on the tissue inside the leaf, eating* it away 

 and producing' a large yellow spot. The grub is found by searching for 

 such yellow spots, and the insect may be seen inside if a spotted leaf is 

 held up to the light. The grub when fidl grown transforms to the pupa 

 inside the leaf and emerges as the beetle. The whole life history is passed 

 within the leaf until the mature beetle comes out to fly about. It feeds 

 upon the leaf, eating away the epidermis and causing further destruction. 



The insect principally attacks the young plants, feeding and laying 

 eggs npon the tender green leaves of the seedling or of the newly trans- 

 planted rice. It is injurious to rice in the seed-bed and shortly after 

 transplanting, the older rice being less attacked and not injured. 



Wild grasses are the normal food-plants and the beetle flies from the 

 waste lands or jungle to attack the early rice. In some parts of Bengal 

 it is reported to come in enormous numbers, blackening the fields on 

 which it settles and causing a wholesale destruction of the crop. Like the 

 rice-bug it is dependent upon moist conditions and attacks rice that is 

 submerged in preference to rice on higher land from which the water has 

 been run off ; this is the only remedy applied by cultivators, who, when 

 possible, let the water out in the hope that the insect will leave their fields. 



The insect spends the winter as a beetle in waste lands and grass- 

 lands. The season at which it appears depends upon the sowing of rice 

 and the climate, but lies between April and November. 



Preventive measures for this pest must be based upon local 

 conditions : where the pest is known to come from a particular place, it 

 may be possible to destroy it there, as, for instance, in the wild grasses 

 in which it lives before the rice is sown, or the sowing and transplanting 

 of rice may be varied to prevent the pest attacking it. In seed-beds the 

 beetle can be destroyed, and if the seed-bed is watched when the beetle 

 is likely to attack it, egg-laying can be prevented. When the beetles 

 come in great number the ordinary bag is sufficient to sweep them up 

 with, and the cultivator is quite capable of using his dhoti or other 

 cloth for the purpose. Any concerted action designed to prevent egg- 

 laying and worry the insect is what is required, and what is, in India, 

 so diflfjcult. When once egg-laying has been performed nothing can be 

 done but to wait for the emerging beetles and destroy them. The use of 

 arsenical insecticides is valuable as a poison for the beetle, but is ineffective 

 against the egg or larva. There is probably little scope for the use of 

 lead arseni9,te, since it will not stand rain and washes off. There is also 



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