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JOURNAL Oh' THE KOYAL llC)K'riCULTU llAL SOOlhrrV 



3. (\Misecii(ive crops oi" swoot [)oUiios alioukl iio(i ])v i^rowii on 

 infeskHl ground. 



4. Tubers that are jiIumUh] (Iccply arc said to be uiore rea-dily adtacked 

 than those planted near the suri'ace. 



0. The importations of tubers shoukl be subject to quarantine, and 

 they shouki be thoroughly examined by a competent authority before 

 tliey are admitted into a new country. 



Cotton- Stainer [Dysdercus ? andreae). 



The only cotton-stainer observed in Jamaica is apparently the rather 

 widely distributed West Indian species Dysdercus andreae (Liim.). 

 This insect literally swarmed in a neglected cotton-field in the parish of 

 St. Andrew ; and in many instances the bolls were almost covered by 

 these brightly-coloured pests. It is scarcely necessary, therefore, to 

 add that the crop was seriously injured by them. It should be pointed 

 out, however, that the field in question had been so grossly neglected 

 that at least one-third of the crop had been completely destroyed by 

 noxious weeds. These conditions were taken as evident signs that the 

 cultivator had lost all interest in the work and had let the ground lapse 

 into a semi-wild state. Questioned as to the destruction wrought by 

 the cotton-stainer, the owner stated that comparatively little haim was 

 done by these pests, providing always that the insects in question were 

 removed from the cotton before the process of ginning. That this 

 statement was inaccurate was proved by an examination of the bolls 

 which showed clearly that they were seriously injured, being for the 

 most part undersized, and the fibre being also brittle and distinctly dis- 

 coloured. 



During the dry season in Jamaica there is evidently a succession of 

 broods and these broods overlap, so that insects in all stages are found 

 living together sometimes upon a single cotton boll. 



In the West Indies the following methods of control have been 

 adopted : — 



1. Baits consisting of little heaps of cotton-seed or pieces of sugar- 

 cane- placed at close intervals between the plants. The insects thus 

 collected together are best killed by dropping them into a bucket con- 

 taining a small quantity of water with a little kerosene added. 



2. The second method, usually adopted when the bolls are well 

 formed, is to jar or shake the plants over a kerosene tin or bucket con- 

 taining the mixture mentioned in 1. 



The insects usually fall from the plants on the least disturbance, 

 so that no great force is needed to dislodge them. Jarring or shaking 

 injudiciously done, as it would be in all probability by the West Indian 

 native, might cause serious injury to the plants, etc. The employment 

 of coolies or strict supervision of the native by a responsible person 

 would be necessary. 



Natural enemies. — Ballou''' says that " Cotton-stainers appear to 

 be remarkably exempt from the attacks of natural enemies," but he 



* Journ. of tlte Imp. Agric. Dept. for the W. Incl., vol. vii. p. 78. 



