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from one block, while in the other they were left undisturbed. After 

 seven months they were again inspected and it was found that in 

 the block where there were no ant nests only 8 trees were infested 

 with the scale, while in another block there were 132 trees infested. 

 In tests to determine the possible protection from parasites afforded 

 by the ant, it was found that on infested plants on which an ants' 

 nest had been placed, no parasitised scales were found, while on 

 plants without ants many scales were parasitised. These experi- 

 ments are not considered conclusive, but it is significant that the only 

 estate in which C. colemani seems to have obtained a persistent hold 

 in Mysore is one where Plagiolepis longipes is found abundantly. 



The most important insect enemies of C. colemani in Mysore are 

 Hymenopterous parasites that oviposit in the body of the host, though 

 the scale continues to Hve and even to reproduce in spite of their 

 presence. Hyper-parasites and ants check the activities of these 

 parasites to a serious extent ; very few of the species concerned have 

 been identified, though text-figures are given of several of them. 

 Certain Coccinellid beetles are more or less predaceous on this scale, 

 the most promising of these being Chilocorus nigritus. These beetles 

 lay eggs on the stem under the scaly bark or on the under-side of the 

 leaf. They hatch in about a week, and the larvae moult three times 

 before pupation, which occurs after about 20 days ; adults emerge 

 a few days later. Both adults and larvae feed on the scale, one 

 larva consuming on an average eight individuals in a day. If, there- 

 fore, this enemy could be introduced in sufficient numbers it should 

 prove an efficient check. Minute mites destroy many of the nymphs 

 while they remain beneath the mother ; their reproductive power 

 is great, but their numbers vary greatly with the locality and the 

 season. The most serious checks to the increase of G. colemani are 

 two fungi. Cephalosjjorium lecanii (white fungus) frequently kills off 

 more than 90 per cent, of the Coccids on coffee estates during normal 

 rainfalls. Empusa lecanii (grey or black fungus) is usually found 

 attacking the scale throughout the early part of the cold weather 

 season, and may continue active until May. While the white fungus 

 is chiefly dependent on mnd and rain for its dispersal, the spores of 

 the black fungus are often projected a distance of one or two inches, 

 thus enabling it to spread even during the drier seasons. 



The host-plants on which G. colemani have been found in Mysore 

 include Alhizzia spp., Wrightia tinctoria, Aegle marmelos (bael fruit), 

 Artocarpus integrifolia (jak-fruit), Mangifera indica (mango), Psidium 

 giuiyava (guava), Citrus spp., Ficus spp., and Eugenia jamholana. 

 The pest is most abundant in years when the north-east monsoon is 

 scanty and a long period of dry weather succeeds it. Dispersion is 

 largely efiected by wind, the young insects being blown as far as 

 450 feet. When artificial methods of control are necessary, spraying 

 and brushing are recommended. The best insecticide is the fish-oil 

 resin soap prepared and sold by the Madras Fisheries Department, 

 used at the rate of 1 lb. to 2 gals, water ; this should be apphed with 

 a pressure sprayer. All nests of ants should be destroyed. Disper- 

 sion of the fungi should be encouraged by tying branches containing 

 them to trees that are free from them. Rapid surface evaporation 

 in young cofiee should be prevented by planting a cover crop and 

 by the proper selection of shade trees. 



