118 



sp. and other native plants ; Baccacoccus elytropappi, gen. et sp. n., 

 on Elytropappits rhinocerotis. 



Keys are given to the South African species of Aster olecanium, 

 Lecaniodiaspis, Cerococcvs and Tachardm. 



MuiR (F). On some African Delphacidae (Homoptera). — Bull. 

 Entom. Research, London, x, no. 2, January 1920, pp. 139-144, 

 8 figs. 



A number of Delphacids are recorded from sweepings from grasses 

 and reeds at Ibadan, Nigeria. These inchide the following new 

 species, which are described : — Drlvhacodcs nigeriensis, D. bridwelli, 

 Dicrnnotropis bridu'elli, D. ibadanensis, Megamelus furcijer var. 

 nigerrevsis, nov., M. Jlavolineaius and Phyllodinus badius. 



Mansfield- Aders (W.). Insects injurious to Economic Crops in 

 the Zanzibar Protectorate. — B>dl. Entnin. Research, London, x, 

 no. 2, January 1920, pp. 145-155, 3 plates. 



A short account is given of the various insects injurious to the 

 economic crops of the Zanzibar Protectorate, which have been the 

 subject of investigations during the last few years. The crops dealt 

 with include cloves and coconuts (the two chief economic products 

 of the Islands of Zanzibar and Pemba), cotton, cereals, vegetables, 

 fruit and shade-trees and timber, miscellaneous plants and stored 

 products. 



Especial attention is devoted to the rhinoceros beetles {Onjctes 

 rhitioceros and 0. boas), which seriously infest coconuts. Young 

 trees from 2| to 3 years old are most usually attacked, many being 

 killed and others partly delayed in reaching maturity. The most 

 useful preventive measi.re is the trapping of the larvae in pits filled 

 with rotting coconut and other vegetable debris and a little manure. 



No definite pests of the clove tree {Eugenia caryophyllata) have 

 been discovered, though the bark of unhealthy trees is attacked by 

 termites {Termes bellieosus) and the dead branches are infested by 

 Bostrychid beetles. A large Tenebrionid. Pycnocerus passerinii, 

 Bertol., is found under the dead bark, but probably does not do any 

 actual damage. 



Tragardh (Ivar). On the Use of Experimental Plots when studying 

 Forest Insects. — BuU. Entom. Research, Loyidon, x, no. 2, Januarv 

 1920, pp. 157-160, 2 figs. 



The method adopted of investigating experimental plots in studying 

 an outbreak of Bi'palus piniarius, L. (pine-tree looper) in Sweden 

 in 1916-1917 is described [R.A.E., A, vii, 423]. It seems Hkely 

 that if other outbreaks are studied in the same way, it will be 

 possible in time to prognosticate after the first year the fate ol forests 

 attacked by this pest. 



Maulik (S.). A new Hispid Beetle injurious to the Oil Palm in the 

 Gold Coast. — Bidl. Entom. Research, London, x, no. 2, January 

 1920, pp. 171-174, 3 figs. 



The Hispid, Coehenomenodera el/ieidis, sp. n., here described is 

 injurious to oil palms {Elaeis guineensis) in the Gold Coast, and is 



