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attacks the crown of the plant and mines the interior. Injections 

 of carbon bisulphide have been recommended, but this treatment is 

 not very practicable. Eotation of crops is almost useless, as this 

 wireworm attacks nearly all plants. The use of cakes of rape-oil 

 dug into the ground in autumn has been advocated, but birds and 

 moles seem to be the only effective check. Macrosiphmn (Aphis) 

 granarium feeds on the stalks and thrips appear on wheat in June, 

 but neither of these is an important pest. 



The Hessian fly [Mayetiolu destructor] is a dangerous pest from 

 April onwards ; from three to six generations occur in a season. The 

 early destruction of stubble that harbours many pupae is advised ; 

 rotation of crops has not given good results, but bearded varieties 

 of wheat are more resistant to attack. A smaller Cecidomyid, Conta- 

 rinia {Diphsis) tritici, appears at the moment of blossoming and 

 oviposits on the spilvcs. The larvae enter the glumes and devour 

 the blossoms, preventing the formation of the grain. In July the 

 larvae descend to the ground, where they pupate and pass the winter, 

 the adults emerging in the following June. Eemedial measures are 

 almost unknown ; the lighting at night of fires into which the adults 

 fly, and the turning over of the top soil to expose the nymphs have 

 been advocated. Bearded varieties are some protection against 

 oviposition ; rotation of crops should be successful, as this species 

 seldom attacks anything but wheat. 



Chlorops lineola is another harmful Dipteron, oviposition occurring 

 at the base of the spikes towards the end of May. The larvae hatch 

 in a fortnight and descend by mining the stalks to the first node, where 

 they pupate. Adults emerge in September and oviposit on the stalks, 

 and the larvae descend down the stem of the plant, causing swelhngs 

 at the base of the stalks, and finally hibernate in the nymphal stage. 

 In infested wheat, the ear seldom succeeds in extricating itself from 

 the leaves and remains green longer than the healthy plants. Such 

 plants are easily detected and should be uprooted and destroyed. 

 Eotation of crops is recommended. An alHed species, Chlorops 

 herpini, only attacks barley. 



Hjonenopterous pests include Cephus pygmaeus, which oviposits 

 below the spike, the larva descending to a few inches above the ground, 

 where it constructs a circular gallery, weakening the plant and hinder- 

 ing its nutrition so that very few ears mature. Pupation occurs 

 below ground, where the winter is passed. Burning the stubble is 

 the only efiicacious remedy. 



Theobald (F. V.). New and little known British Aphides. — Entomolo- 

 gist, London, lii, no. 674, July 1919, pp. 157-161. 



The following species are dealt with : — Myzus gei, sp. n., alate 

 females of which were found under leaves of Gemn urbanum, sur- 

 rounded by small green larvae ; Myzus mercurialis, sp. n., found 

 in abundance on Mercurialis officinalis in the spring ; M. galiifolium, 

 sp. n., living in dense clusters on the top shoots of bedstraw {Galium 

 cruciatum)' Aphis ahrotaniella, sp. n., taken on Artemisia abrotani; 

 Macrosiphum solanifolii, Ashm., which oviposits on roses in the 

 autumn, the alate forms migrating to potatoes in June and July ; 

 and Myzus solani, Kalt., very abundant and causing damage to 



