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Report on the Occurrence of Insect and Fungus Pests on Plants in 

 England and Wales in the Year 1917. — Bd. Agric. Fisheries, 

 London, Miscell. Publications, no. 21, 1918, 32 pp. 



The chief insect pests on crops in England and Wales during 1917 

 were : — Diptera. Mayetiola destructor. Say (Hessian fly), on wheat, 

 especially the " Sensation " variety ; Hylemyia coarctata, Fall., causing 

 extensive injury to winter wheat, wheat following potatoes being 

 most frequently attacked ; Hylemyia antiqua, Meig. (onion-fly), a 

 serious pest in almost every district, plants from early sown seeds 

 being less Hable to attack ; Chlorops taeniopus, Meig. (gout fly), 

 responsible for much damage to barley in the eastern and midland 

 counties ; Oscinella [Oscinis) frit, L. (frit fly), causing severe and 

 wide-spread damage to wheat and oats, especially when the latter is 

 grown after grass ; Agromyza graniinis, Kalt. , the larvae being reported 

 as mining wheat-leaves ; Pegomyia betae, Curt., a serious and wide- 

 spread pest of mangels, also attacking sugar-beet in Lancashire ; 

 Contarinia otiobrychidis, Kiei^'., attacking sainfoin in the eastern 

 counties ; Phorbia {Chortophila) brassicae, Bch. (cabbage-root fly), 

 causing considerable and wide-spread damage, in one case tarred discs 

 failing to give protection, while in another a mixture of naphthaline 

 and lime scattered round the plants prevented attack ; Psilo, rosae, F. 

 (carrot-fly),- abundant in Cheshire, even on plots treated with tar-oil, 

 also attacking parsnips ; Acidia heradei, L. (celery-fly), recorded 

 from most districts, damaging parsnip and celery ; and Contarinia 

 {Diplosis) pyrivora, Ril., causing much loss in pears in many districts. 



Rhynchota. Calocoris norvegicus, Gmel. {bipunctatus, L.), Lygus 

 pratensis var. campestris, Fall., and L. pabtdinus, L., causing wide- 

 spread damage to potatoes ; the Capsid, Plesiocoris rugicollis, Fall., 

 causing damage to apples by malformation and distortion ; Aleurodes 

 brassicae, Wlk., abundant on cabbages in the west of England ; 

 A. vaporariorum, Westw., seriously injurious to tomatoes in the Isle 

 of Wight, where it was controlled without injury to the plants by 

 fumigation with hydrocyanic acid gas, | oz. sodium cyanide being 

 sufficient for each 1,000 cubic feet of space ; and Pseidococcus 

 aceris. Sign., recorded from apples in Kent and Sussex. 



The Aphids recorded include : — Trama troglodytes, Heyd., on the 

 roots of artichokes in Kent ; Macrosiphum granariuni, Kirb. , very 

 abundant and causing considerable damage to wheat and oats 

 in the eastern counties ; Macrosiphum solani, Kalt., Wiopalosiphum 

 solanella, Theo., and Myzus solanina, Pass., reported as harmful 

 and abundant on potatoes in several southern counties ; Aphis rumicis, 

 L., recorded from Shropshire and Yorkshire on root-crops and also 

 on beans in the north of England ; Rhopalosiphimi dianthi, Schrk., 

 causing considerable damage to turnips in Yorkshire, swedes being 

 comparatively immune, even when grown in the same field ; Callipterus 

 ononidis, Koch (C. trifolii, Mon., Chaitophorus maculatus, Buckt.), 

 known as the yellow clover aphis in America, and occurring also in 

 India and Egypt, recorded from red clover in two localities ; 

 Pemphigus Icuctucarius, Pass., reported as causing considerable damage 

 to lettuces in widely separated localities ; Aphis mali, F., and 

 A. malifoliae, Fitch, plentiful in Kent and Worcester during July ; 

 A. pruni, Koch, very injurious to plums in Wiltshire ; Hyalopterus 



