520 



borer, Xylotrechus quadripes, Ch., ought to be definitely ascertained. 

 Unfortunately it does not show much sign of multiplying in the 

 plantations after liberation, being largely influenced by adverse 

 weather conditions and by the attacks of natural enemies. D. picticeps, 

 Kieff., has practically disappeared since 1920, probably owing largely 

 to the destruction of unhealthy coffee stems by burning, but more are 

 being reared on infested teak for distribution on coffee. D. tristriatus, 

 Kieff., has proved as yet too difficult to rear for plantation tests to be 

 made, but it is hoped to get better results in 1922. 



Ichneumonid parasites have been very scarce during the period 

 under review. The Evaniid, Pristaulacus nigripes var. dnporti/Kiefi., 

 has been reared on infested coffee, but has produced no result when 

 placed upon fresh stems of infested coffee. The Bethylid, Sclerodermus 

 domesticus, Latr., is considered the most efficient enemy of the borer, 

 and is being reared in large numbers. Up to 15th May, in 1922, 

 16,000 individuals had been liberated in the plantations. 



In addition to infested coffee stems for the rearing of parasites, 

 other plants are being used, such as teak, Oroxylon indicum, Randia 

 dumeforuni, etc., as well as bamboo attacked by Chlorophorus annularis. 



Experiments with repellents against X. quadripes are still being 

 continued ; none has as yet given much success. 



Another insect that has been observed living within the branches 

 of coffee is a species of Collyris, probably C. fuscitarsis, Schm. ; an 

 allied Cicindelid is known as a minor coffee pest in Java and British 

 India [R.A.E., A, v, 122, 164]. 



Hall (W. J.). The Hibiscus Mealy Bug {Phenacoccus hirsutus, Green). — 

 Egypt Minist. Agric, Cairo, Tech. & Sci. Ser., Bull. 17, 1921, 

 28 pp., 1 map, 6 plates. [Received 19th August 1922.] 



This bulletin gives in a more extended form than has previously 

 been noticed [R.A.E., A, x, 449] a good deal of information regarding 

 Phenacoccus hirsutus, Green (hibiscus mealy-bug) . A list of the food- 

 plants most commonly found is given, divided into 28 species of 

 primary, food-plants, i.e., plants on which the mealy-bug thrives and 

 breeds rapidly ; secondary food-plants, numbering 43, on which 

 breeding occurs, but which rarely become very badly attacked unless 

 close to a heavy infestation ; and 31 tertiary food-plants, on which 

 the pest is rarely found and to which it never does any serious damage. 

 The transport of plants and fruit from infested areas is the chief 

 method of distribution of the pest before its presence becomes well- 

 kno^vn. Wind can undoubtedly carry the insect over long distances, 

 and it is rather significant that it has spread considerably further to 

 the south than to the north- — the prevailing wind being from the 

 north. Birds also convey infestation by transporting young larvae or 

 eggs on their bodies from tree to tree. 



Particulars of fumigation experiments are described, this method 

 not proving very practicable. A paraffin emulsion is recommended, 

 consisting of 2 gals, paraffin to 1 gal. of water, with I lb. soap. This 

 may be used in varying dilutions from 1 in 15 to 1 in 50 ; the most 

 effective for general work was 1 in 15, in which case 1 lb. soap was 

 used. A spray of 40 lb. unslaked lime, 20 lb. sulphur and 15 lb. salt 

 in 60 gals, of water is advised for winter work ; this is rather more 

 expensive than the emulsion. 



No parasite of P. hirsutus has been reared from it in sufficient 

 quantities to promise any success as a control. The commonest 



