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soil should be thoroughly dug up at the end of the season to ex- 

 pose aestivating Earias pupae. The cotton-stainer, Difsdercus super- 

 stitiosus, F., was found in some numbers during the dry season, but 

 D. nigrofasciatus, Stal, D. melanoderes, Karsch, and Oxycarenus 

 dudgeo7ii, Dist., were not abundant. D. super stitios us SindD.inelano- 

 deres occasionally interbreed. Small nets were successfully employed 

 for collecting immature cotton-stainers, the larger net used in the 

 West Indies being found impracticable. Shaking the insects into wide- 

 mouthed tins containing water and a little kerosene is a simple method 

 suitable for the native farmer, but hand-picking is probably the most 

 efficacious method of control. Mixed cultivation decreases the spread 

 of insect pests, though other Malvaceae should only be planted in 

 the vicinity as a trap, okra being especially recommended for this 

 purpose. Intercalated rows of maize serve as a protection. 



Among cacao pests, colonies of a Psyllid, Udamostigma tessmanni, 

 Aulm. var., occurred, but were successfully combated by brushing with 

 kerosene emulsion. Black Aphids were effectively checked by natural 

 agencies. The chief insect pest was a Rutelid beetle, Adoretus hirtellus, 

 Castn., which invariably attacks young plants, feeding by night and 

 hiding by day, often about the roots. Other pests of cacao leaves 

 were : — Zonocenis variegatus, L., a Melolonthid, Trochalus carinatus, 

 Schonh., and the caterpillars of Metisa sierricola, White, Diacrisia 

 maculosa. Cram., and Earias citrina, Saalm. The ant, Oecophylla 

 smaragdma longinoda, Latr., is probably invaluable in keeping off 

 insect pests other than Coccidae. To combat these leaf-eaters, the 

 plants were dusted in the wet season with a mixture of Paris green 

 and lime ; later on, spraying with lead chromate in solution was sub- 

 stituted to avoid scorching. The caterpillars of Eulophonotus 

 myrmeleon, Feld., were the only cacao stem-borers found ; in order 

 to kill the larvae tunnelling in the main stems, injections of carbon 

 bisulphide were made into the bore-holes, which were immediately 

 plugged with a pellet of clay and tarred. Special search was made 

 for the boring beetle recorded as attacking cacao on the Gold Coast, 

 but it was not found. Some trees showed evidence of attack by what 

 was almost certainly the larva of an Aegeriid moth. Sahlbergella 

 theobromu, Dist., occurred sparingly. A species oiPseudococcus, either 

 longispinus, Targ., or virgatus var. madagascariensis occurred, but was 

 effectively checked by the caterpillars of a butterfly, Spalgis lemolea, 

 H. H. Druce ; brushing with kerosene emulsion was found less 

 harmful than spraying. Slictococcus sjosledli, Newst., is protected by 

 Oecophylla ; its natural enemies include the caterpillars of the moths, 

 Eublemma ochrochroa, Hmp., and Tortrix callopista, Durrant, and at 

 one place this scale showed signs of parasitism by Chalcids. 

 S. dimorphus, Newst., occurred, probably owing to the use of 

 Cajanus indicus for shade purposes, but was greatly checked by 

 Eublemma scitida, Ramb. The Anthribid beetle, Araecerus fascicidatus, 

 de G., and a Noctuid, Characoma stictigrapta, Hmp., were not un- 

 common attacking the pods. Slictococcus dimorphus, Newst., 

 occurred especially on the yellow Amelonado cacao, and was 

 guarded by the red ant. Ceratitis nigra Grab., was captured in great 

 abundance, but its relation to the pods was not determined. A 

 large ant, PaUothyreus tarsatus, ¥., was useful in carrying off the 

 termites, which were successfully combated with the " Universal 



