PROCEEDINGS OF THE THIRD EXTOMOLOGICAL MEETING 921 



may be seen closer to the upper node than to the lower and also far above 

 the level of the impression left by the oviposition on the outer sheath. 



The grub as soon as out of the shell travels about in the hollow and on 

 reaching the base feeds a little on the pithy lining of the inner wall. It 

 next attends to the ringing of the stem, which is begun on the second or 

 third day after hatching and is accomplished in a few hours. The cut 

 goes completely round and is so deep that it almost reaches the epidermis. 

 The question that arises is " what purpose does this ring serve ?" 

 The labour bestowed and the skill displayed premise something more 

 than an effort to supply with humble toil the modest wants of the day. 

 In all probability it is intended to prevent the plant-sap from rising up. 

 From now the grub is to be found above the ring. It is a moderate 

 feeder and does not go about in search of a palatable morsel. Remaining 

 above the ring and content with the adjacent tissue, as it grows it finds 

 itself in an enlarging chamber. If the grub gets moist it is sure to die. 

 This calamity is prevented by the ring which prevents plant-sap from 

 rising up and by the accummulation of frass at the ring. 



It may be noted here that a single stem may be infested with more 

 than one grub. There may at times be as many as four. But always 

 • there is only one grub in an internode and it never bores through into an 

 adjacent one. 



When full-grown the grub pupates within the stem. If the stem now 

 snaps at the ring, as occasionally happens, the mass of frass accumulated 

 there, as mentioned before, acts as a plug and keeps the pupal chamber 

 closed and the pupa safe. 



The beetle on emergence has the exoskeleton soft and of an amber 

 colour. But very soon the normal hardness and hue is gained and within 

 five days after emergence the full-fledged adult cuts a small hole in the 

 wall of the stem and creeps out. 



The beetles are shy creatures, but a close observer can locate them, 

 moving up and down the leaves or stems. They seldom take to flight, 

 a habit which makes hand-picking easy when control methods are 



V. Conclusion. 



It may be stated in conclusion that the beetle has habits well calculated 

 to ensure success. Eggs are laid during the second month of the crop 

 and they grow into adults in a month and a half. A generation is there- 

 fore produced before it is time to harvest the crop. 



