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(black weevil borer of banana) with a view to its control in tliat and 

 other countries. Bananas and plantains in St. Lucia are grown chief!}' 

 in scattered clumps among the vegetable plots of peasant proprietors, 

 in small clumps on some estates, or as the remains of primary shade 

 or wind-belts on cacao estates. C. sordidus was found wherever the 

 different varieties of bananas were examined. Young plants in their 

 first season show no weevil infestation ; the older stools, especially 

 those in an abandoned or neglected condition, show the highest degree 

 of infestation. All varieties were attacked, but plantains seemed to 

 be preferred. This variety is gradually being replaced by the makabou, 

 which it is hoped may be less susceptible to weevil attack. When 

 plantains have ceased to produce good bunches of fruit, the clump 

 is frequently left standing, chiefly to supply young suckers for planting ; 

 it also serves as an ideal breeding place for the weevil. A description 

 is given of the condition of a typical neglected and overgrown stool of 

 plantains infested by the weevil ; the oldest bulb was found to be the 

 worst infested, stumps left from cut stems had theif bulbs riddled with 

 tunnels ; bulbs of stems in the early fruiting stage were usually attacked 

 by borers in all stages of development. Yomig suckers of different 

 sizes were growing all over the clump : the larger ones were sometimes 

 slightly attacked on the side nearest the infested parent bulb, but as a 

 rule the weevils are apparently not attracted to young suckers. Several 

 recently planted suckers were examined for weevil grubs, but none 

 were found. Adult weevils could usually be foimd in the older clumps 

 of all varieties of bananas, generally hiding in the rubbish at the base 

 of the stems or between the leaf-sheaths near the ground. In no 

 instance were adult weevils found attacking young plants. 



In view of these facts, it would appear that there is a period in the 

 life of the banana plant when it is most attractive to the egg-laying 

 weevil, this period being more or less contemporaneous with the 

 reproductive period of the plant, during which time the bulb is being 

 drawn upon in order to produce the future bunch and to supply the 

 suckers with nourishment. That is, the weevil begins to oviposit on 

 the plant about the time that the flowering shoot is in process of 

 developing, with the bulb as a reservoir of food for the future bunch, 

 and continues to breed in the bulb until the tissue has begun to 

 deteriorate. This process of deterioration may be hastened by disease 

 and by the attacks of the grubs themselves. During this period of 

 infestation the weevil probably passes through several generations, 

 the bulb being more and more riddled with each successive one. 

 Unless, therefore, the banana plant gets a good start at first and is 

 able to develop its flowering shoot at the normal time, a weevil attack, 

 perhaps assisted by disease, will have time to injure the bulb seriously 

 enough to prevent the development of a good bunch. If, however, 

 the plant is kept healthy and vigorous until the bunch is well formed, 

 it should be able to withstand an attack by the weevil, and still produce 

 a normal bunch of fruit. 



No new remedial measures against C. sordidus have been discovered 

 as a result of these investigations in St. Lucia. The importance of 

 good cultivation can only be further emphasised. It is pointed out 

 that small growers frequently expect their plants to produce the 

 maximum amount of fruit with the least possible attention, but this 

 lack of attention merelv results in undersized bunches that are valueless 



