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as possible to the parent cutting. They then opened the shoot and 

 destroyed the fat grub. In some cases, however, the grub had mi- 

 grated to a fresh shoot which as yet did not show any sign of decay 

 and thus escaped " Eoth adds that " while dirty fields were being 

 destroyed wholesale by the grub, clean fields were not infected to any 

 such extent." 



A very striking instance in which the moth-borer (or a very closely 

 allied species) was successfully dealt with came under the notice of 

 Kew from the Island of Teneriffe. 



In the South-western corner of this island a very large sugar estate 

 has been established and is now under the management of Mr. Richard 

 Tonge of the Icod and Daute Estate Company. On this estate the canes 

 were very severally attacked by moth-borer, which was believed also to 

 attack the maize crops of the island. The injuries to the sugar-canes 

 were becoming yearly more and more serious. Mr. Tonge was in 

 despair. He carefully studied the habits of the insects and then or- 

 ganised a system of treatment which was steadily pursued for two years. 

 Every person engaged on the estate was taught to recognise at a glance 

 the successive stages of the insect, viz., the grub, the chrysalis, and the 

 mature insect. A small sum was offered for these and payment was 

 made at the close of each day. During one month (February, 1893) 

 there were destroyed 46,884 insects in various stages. During the 

 rest of the year, the numbers were not so large, but the record kept of 

 them shows that 9,640 grubs were cut out of standing canes, 5,022 

 were destroyed in the chrysalis stage, and 1,144 moths were caught 

 on the wing. By judicious management and, personal influence, Mr. 

 Tonge has so thoroughly enlisted the interest of the workpeople that 

 the moth-borer is becoming less and less plentiful. Its practical ex- 

 termination on this estate is now only a question of time. The period 

 during which the canes are growing appears to be the most critical 

 time. TVomen and children are then kept regularly employed in cut- 

 ting out any canes attacked by the moth-borer, and the grubs are des- 

 troyed in their burrows. This is regarded as the most effective plan. 

 It is believed that if this plan alone were regularly pursued in the 

 West Indies for two or three seasons, the injuries would be reduced 

 within comparatively small dimensions. 



As regards other means for destroying the moth-borer, Mr. Barber, 

 in his letter already cited has added the following interesting points, 

 which deserve consideration. These do not, however, show that the 

 planter should relax his efforts to cut out the grubs in the standing 

 canes. Nothing can do away with the necessity for this. Mr. Bar- 

 ber's remarks exhibit a careful study of the habits of the insect, and 

 draw particular attention to the need for adopting only such remedies 

 as are suited to local circumstances. Countries situated in the tropics 

 where there is no winter's rest for the canes, obviously require a dif- 

 ferent treatment from that found suitable in the Southern United 

 States and others where canes are only growing during about seven or 

 eight months in the year. In these respects the remedies suggested in 

 the extract from the Indian Museum notes require some modification. 



Mr. Barber remarked, in his Report to the Government, of April 

 16th :— 



" The question of burning has, I believe, been much obscured by the 



