101 



Owing to weather conditions, an outbreak of Ceratitis capitata 

 (Mediterranean fruit fly) occurred on late peaches. All infested fruit 

 was burned and the ground round the trees treated with carbon 

 bisulphide to kill the pupae in the soil, but this method had to be 

 abandoned owing to the extent of the area infested. The history 

 and habits of this fly are briefly described. A successful bait is a 

 mixture of treacle or sugar and water with lead arsenate sprayed over 

 the trees. Unfortunately bees take this poison as well ; all hives 

 should therefore be removed as far as possible from trees thus sprayed. 



Complaints have been made that lead arsenate is not effective as a 

 spray for codling moth [Cydia pomonella]. The reason for this may be 

 that no precautions are taken in Tasmania against the second generation 

 of this pest, which always occurs in hot and dry summers, the larvae 

 appearing at the end of January, and the adults emerging in the 

 spring. Sprays may also be wasted by not being applied at the right 

 time, i.e., when the petals have fallen and the calyx is opening. 



Pests of stored grain or chaff include Silvaniis surinamensis (saw- 

 toothed grain beetle), Calandra granaria and C. oryzae. Fumigation 

 with carbon bisulphide or hydrocyanic acid gas is recommended for the 

 first named. It is urged that barns should be constructed that can be 

 thoroughly fumigated. Samples of prepared cereal foods have been 

 received infested with Mediterranean flour moth [Ephestia kiihniella]. 



Cabbages and allied plants were considerably damaged by Plutella 

 maculipennis {cruciferarmn) (cabbage moth), which has increased 

 abnormally owing to a series of hot summers. The measures recom- 

 mended are dusting with a mixture of soot and lime or spraying with 

 hot water at a temperature of 120°. Paris green and lead arsenate 

 are eftective sprays, but dangerous for use on vegetables, an infusion 

 of hellebore being a much safer remedy. 



Bodkin (G. E.). [Report of the Government Economic Biologist.] 



— Ann. Kept. Dtpt. Sci. S- Agric. [Brit. Guiana], 1919, George- 

 town, 1920, Appx. iii, 9 pp. [Received 29th December 1921.] 



The control of sugar-cane pests in British Guiana largely depends 

 on an adequate labour supply, and there is little alteration in their 

 status. Continued investigations are being made for the control of 

 the moth borer [Diatraea saccharalis] by artificially increasing its egg- 

 parasites. 



During 1919 rice was damaged by an insect thought to be identical 

 with or very closely allied to Lissorhoptriis simplex, Say (rice water 

 weevil). Scapteriscus vicinns. Scud, {didactylus, Latr.) was thought to 

 be damaging young rice plants, but further investigations proved the 

 injury to be due to Laphygma fntgiperda, S. & A., the caterpillars of 

 which feed by night. 



Pests of coconuts include Brassolis sophorae, L., Sihine fiisca, Stoll, 

 and Castnia daedalns, Cram. 



Seeds of ornamental palms shipped to the Dutch East Indies from 

 British Guiana w^ere found infested with Pachymerus [Caryohoriis) 

 nucleorum, F. 



The Coccids recorded during the year were: — Aspidiotits palmae, 

 Morg. & Ckfl., on palms; A. secretus, C\d\., onhdivahoo ; M organella 

 {A.) longispina, Morg., on bark of papaw trees; A. rapax, Comst. 

 {camelliae. Sign.), Chrysomphaliis apicatiis, Newst., and Pulvinaria 

 brevicornis, Newst., on bark of Avicennia nitida ; Pseiidococcns 



