128 



Aders (W. M.). Entomology in Relation to Agriculture.— Zanzibar 



Protectorate Med. & Pub. Health Repts. for 1915 ; Zanzibar, 1916, 

 pp 49-51. 



Insect pests did not cause any serious outbreak in the year under 

 review, but those recorded in pre\'ious years occurred more or less 

 throughout the season [see this Review, Ser. A, iii, p. 124]. 



The most prevalent pests of citrus trees are various Coccids, of which 

 the following have been identified : — Icerya seychellarum, J. jpurchasi, 

 Pseudococcus citri, Coccus (Lecanium) viridis, Pseudaonidia (Aspidiotus) 

 trilobitiformis, Lepidosaphes beckii (citricola) and Dactylopius obtusus. 

 Spraying with fish-oil has given fairly good results, especially on young 

 trees. 



Insects injuring economic plants dm-ing the year include : — Diptera : 

 Larvae of Dacus brevistylus, Bezzi, D. vertebratus, Bezzi, and D. punctati- 

 frons, Karsch, in Cucurbitaceae ; Ceratitis rosa, Karsch, bred from 

 soursop. Lepidoptera : Chilo suppressalis,W\k. , the larvae of which feed 

 on maize cobs and tunnel in the main stalk ; Duomitus capensis. Baker, 

 the larvae tunnelling in castor-oil plants ; Miresa melanosticta, Baker, 

 the larvae of which are found abundantly feeding on leaves of 

 Tenninalia catappa (African almond). Coleoptera : Tenebr aides 

 mauritanicus, L., in various stored grains ; Cossonus suturalis. Boh., 

 in stored sweet potato tubers ; Necrobia rufipes, de G., adults and 

 larvae of which feed on stored copra, causing considerable damage. 

 A list of the Coccids infesting various trees is given. 



Speyer (E. R.). Agricultural Investigations in Ceylon. — Trap. 

 Agriculturist, Peradeniya, xlviii, no. 6, June 1917, pp. 347-348. 



Egg parasites of the tea tortrix \Homona coffearia] have been studied 

 and bred successfully in the laboratory and this work is being continued 

 under more natural conditions in Maskeliya. Icerya purcJiasi (fluted 

 Lcale) is increasing in spite of predatory Coccinellids and the fungus, 

 Cephalosporium. For the control of Xyleborus fornicatus (shot-hole 

 borer of tea) an experiment has been tried of pruning infested bushes 

 in order to anticipate a severe attack ; this did not prove successful 

 from the economic point of view, but the results prove that the 

 prescribed periods when extra prunings should take place are entirely 

 coirect. It is important that all woody portions of prunings should 

 be burnt immediately after pruning. Experiments with washes have 

 been continued and a partly satisfactory paint composed of fish-oil 

 and resin has been obtained ; these investigations will be completed 

 during the next pruning season. X. fornicatus has been found for the 

 first time in the dead-wood of the Ceylon almond, Terminalia. This 

 discovery is important, as it is the first indication of the possibility of 

 using a successful trap. Several other Scolytids have been found and 

 received from dead rubber trees and from Grevillea, Albizzia and 

 Tephrosia. 



Speyer (E. R.). The Fluted Scale {Icerya purchasi). — Trop. 

 Agriculturist, Peradeniya, xlviii, no. 6, June 1917, pp. 355-358, 

 Ifig. 



Icerya pur chasi (fluted scale) was first discovered in Ceylon in 1915 

 on Acacia decurrens and later on Casuarina trees. By August 1916 



