AN INSECT TROUBLESOME IN UGANDA 87 



buds ; unless they occur in very large numbers they 

 do not cause serious damage to more mature parts of the 

 tree. Combative measures should be adopted similar 

 to those recommended in regard to thrips. 



Ceratitis punctata, Wied, attacks cocoa fruits in Ashanti, 

 Gold Coast, and also in Uganda. According to Gowdey 

 (Government Gazette, Uganda, October 1909) this insect 

 belongs to the Trypetidce, a dipterous or two-winged 

 family of vegetable-eating insects. 



The female lays its eggs under the peel of the cocoa 

 fruit. Larvae hatch out from these in from twelve to 

 fifteen days, and at once commence feeding upon the 

 interior tissues of the fruit and interfere with the develop- 

 ment of the seeds. 



These larvse measure about half an inch long when 

 fully grown, and are then fifty-five or sixty days of age. 



They are footless, colourless, twelve-segmented grubs, 

 with prominent dark-coloured mandibles. They pupate 

 in the soil at a depth of 2 in. near the stem of the tree. 

 The puparium varies in colour from white to pale brown ; 

 it is barrel-shaped and segmented. The pupal stage 

 lasts from fifteen to seventeen days. 



The ground colour of the adult insect is yellowish 

 white ; it has eyes red or purplish, thorax beautifully 

 striped and spotted, abdomen, except basal segment, 

 spotted and with black bristles at apex, wings with 

 fuscous bands and dark spots. 



They appear to feed upon any sweet substance. There 

 seems to be no sharply defined season between the broods, 

 and breeding is continuous as long as food is available. 



The microscopical examination of several females 

 disclosed the presence of an average of fifty eggs each. 

 As it is considered there are four broods a year it will 

 be observed that if every egg resulted in an adult the 

 descendants from a pair of flies at the end of the year 

 would number 390,625. This number is only based on 

 theory, and would of course never be actually attained. 

 Fruits other than cocoa in which the females lay their 

 eggs are : mango, melon, guava, and passion-fruits. 



As the adult insects are attracted by sweet substances, 

 control measures should take the form of poisoned baits 

 of sweet liquids. Gowdey recommends a mixture con- 

 sisting of : 3 Ib. sugar, | Ib, arsenate of lead, and 5 gallons 



