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Irequently die. Since the life cycle occupies sonietliiug- over a year the 

 damage is wrought at no particular season. Although the life history 

 is not yet thoroughly worked out, it is certain that the larva at the 

 completion of its stage of growth hollows out a chamber of sufficient 

 size among the larger roots and stalk bases, using the frass to form a 

 sort of coarse cocoon in which it undergoes the comparatively brief pupal 

 stage. 



The adult beetles seem to be strongly attracted to the "gauigaui" 

 trees (Sesbania grandiflora) and in some districts immense numbers of 

 them may be seen or heard flying about these trees in the evening. For- 

 tunately this pest is attracted to strong lights and, therefore, it may be 

 successfully combated by the use of trap lights placed in or near the 

 cane field. These lights should be raised a meter or more from the 

 ground and underneath each light there should be placed a pan as broad 

 as possible containing water and a small quantity of petroleum. Any 

 large or brightly burning lantern will suffice; generally speaking, the 

 stronger the light the greater will be the nmnber of beetles caught in 

 the pans. 



One of the principal causes of the prevalence of these insects in cer- 

 tain districts is the practice of leaving the stubble in the ground for 

 several seasons. Any field believed to be infested with this pest should 

 be plowed and thoroughly harrowed as often as possible, the roots of 

 the old canes being removed from the soil and burned. The use of 

 animal manures should also be avoided as these undoubtedly attract the 

 mature insects when about to deposit their eggs. 



It is said that applications of kainit or other potash compounds will 

 kill or drive away grubs from the cane roots. 



Tip borer {Scirpophaga intacta Snell. Pyralidae). — This small white 

 grub, usually entering near the tip of the cane, is the larva of a small 

 white moth having a tuft of brownish hair on the underside of the 

 abdomen. The eggs are laid on the leaves near the top of the canes 

 and are covered by a mass of cinnamon-colored hair which is rubbed 

 from the abdomen and plastered over the egg mass, thus protecting the 

 eggs more or less from enemies and water. The larva when hatched bore 

 through the rolled-up leaves and eat their way downward through the 

 stem, often going through two or three joints. After attaining its full 

 size it eats its way through the rind of the cane and after spinning a 

 web across the entrance to its burrow it finally attaches itself to the 

 wall of its chamber by fine silky threads and there undergoes the pupal 

 stage. It may be that this species is a variety of S. auriflua Zell., the 

 only difference being that in the before-mentioned species the fringe of 

 hair is brown while in the latter one it is buff in color. The moths 

 may be noticed during the daytime resting on the underside of the leaves 



