WHOLE VOL. APPLIED ENTOMOLOGY HOWARD 517 



Dr. A. D. Imms, of Harpenden, England, who visited the islands 

 in 1925 and who published an account of his observations in the 

 Annals of Applied Biology for August, 1926 (pp. 202-423). This 

 paper is presented in a masterly way, and should be read. He ends 

 with a summary which may well be printed here : 



1. Insect pests in the Hawaiian Islands are, with few exceptions, immigrant 

 species from other countries. Their control by biological methods dates from 

 1890, when A. Koebele introduced Notniis cardinalis for repressing the cottony- 

 cushion scale, Iccrya purchasi, and the experiment was completely successful. 



2. The sugar cane leaf-hopper, PerkinsicUa saccharicida, has been suppressed 

 by the combined activities of several imported species of Chalcid egg-parasites, 

 followed by the introduction of the predaceous Capsid, Cyrtorhinus munduJus, 

 from Fiji and Queensland. 



3. Satisfactory control of the sugar cane borer, Rhabocnemis obscura has 

 been achieved in most infested areas by the Tachinid Cerotimsia sphenophori, 

 introduced from New Guinea. In certain districts, under bad climatic conditions, 

 outbreaks still occur and efforts are being made to meet the situation by intro- 

 ducing other beneficial insects. 



4. Efficient control of the beetle, Anomala oricntalis has been obtained by 

 the introduction of the wasp, Scolia manilae from the Philippines. This pest 

 has not since increased to its former destructive proportions. 



5. The Avocado mealy-bug, Pseiidococcus nipac, accords one of the most 

 recent examples of biological control. Since the importation of the Chalcid 

 parasite Pscudaphycus utilis from Mexico in 1922 this pest has been difficult to 

 find in many districts. 



6. The indigenous Pyralid leaf-rollers, Omiodcs accepta and O. blackburni, 

 are no longer pests of serious consequence. They are controlled by several 

 enemies, chief among them being the Braconid, Macrodyctium om'wdivorxim and 

 the Chalcid, Chalcis obscurata; both parasites were originally obtained' from 

 Japan. 



7. Satisfactory repression of the Mediterranean fruit-fly, Ccratitis capitata, 

 has yet to be achieved. The importation of parasites from Africa and Australia 

 has markedly decreased the infestation, but their efficiency appears to be partly 

 neutralized by the species competing against one another and supra-parasitism 

 is prevalent. 



8. The Australian fern weevil, Syagrius jtilvitarsis, no longer occasions 

 damage to tree ferns to its former extent. The recent introduction of the 

 Braconid Ischiogonus syagrii from Australia has brought about this result. 



9. Early introductions of the various Coccinellidae, more particularly of 

 Cryptolactmts montroitsicri and Coclophora inacqualis, resulted in the complete 

 subjugation of certain coccids and aphides. 



10. Promising results are being obtained against army worms and cutworms 

 by the recent introduction of the Chalcid Euplcctnis platyhypcnac from Mexico. 

 The breeding and liberation of this parasite are still being carried out. 



11. Control of wireworms and the horn fly has not, so far, met with success. 

 * * * 



It seems that more than 90 dififerent species of beneficial insects 

 have been successfully introduced into Hawaii from other countries. 



