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with hydrocyanic acid or painting the hot-water pipes with sulphur 

 are useless against this pest. The leaf-miner, Phytomyza geniculata, 

 Macq., is a serious pest and outbreaks of it are common. Hand- 

 picking and burning infested leaves gives good results, but this must 

 be properly carried out by all growers in the same locality or reinfesta- 

 tion is certain to occur. As a protective spray in May and June, 

 1 pint carbolic acid and | lb. soft soap in 100 gallons water may be 

 used ; if the leaves are tender, quassia should be substituted for 

 paraffin emulsions. The only really satisfactory insecticide is tobacco 

 extract or nicotine sulphate ; eggs, larvae and pupae are killed by 



1 part of nicotine in -100 parts of water. The greenhouse whitefly, 

 Aleurodes raporarioriwi, Westw., is a serious greenhouse pest. Plants 

 outside also became infested and reproduction out of doors goes on 

 until cold weather sets in, a complete generation occupying about five 

 weeks. Fumigation with hydrocyanic acid is the most efficient 

 control measure, but where this cannot be undertaken, repeated fumi- 

 gation with tobacco may be resorted to ; half a pint of fir-tree oil in 



2 gallons of water makes an effective spray ; special care must be 

 taken to wet the underside of the leaves. Saissetia liemisphaerica, 

 Targ., can only be controlled by spraying with water under strong 

 pressure ; soft soap and water is fairly effective against this scale, as 

 also is a soap-paraffin emulsion made from 8 lb. soft soap and 5 gallons 

 of paraffin boiled together in a closed vessel with 1 pint of water added 

 when boiling ; for use, 10 lb. of the jelly which results when cool, is 

 dissolved in 40 gallons of water ; all badly infested plants should be 

 destroyed. The froghopper, Apkrophora cilni, may be controlled by 

 spraying with a 1 per cent, solution of tobacco extract followed by 

 dustmg the young shoots and buds with sulphur. These measures 

 should be repeated every fortnight from March to September. The 

 same treatment may be applied against the chrysanthemum bug, 

 Adelphocoris lineolatus, Goeze. Lucerne, onions, beet and certain 

 weeds are also food-plants of this pest. The greenhouse Orthezia 

 {Orthezia insignis, Douglas) can be controlled by spraying with fir oil 

 and water, or dipping the plant. Fumigation with hydrocyanic acid 

 is the best remedy where practicable. Against Enarmonia mimdana, 

 Hb., the same treatment as for A. lineolatus is useful ; all attacked 

 flower buds should be picked of! and destroyed ; hibernating larvae 

 may be destroyed by injecting sulphiu'otted hydrogen into the soil in 

 autumn. This may also be done against Fdtia exclamationis, L. 

 Arsenate of lead as a fine spray will destroy the larvae ; this may be 

 made according to the following formula : — Acetate of lead, 7 oz. ; 

 pure arsenate of soda, 5| oz. ; water, 10 gallons. The larvae of 

 Hepialus lupulinus, L., often damage the underground parts of several 

 cultivated plants besides chrysanthennims ; vaporite is of some value 

 against them and, in confined areas, injections of carbon bisulphide 

 into the soil ; pieces of potato buried a few inches below the surface 

 serve as traps. Three species of eelworm, Aphelenclms olesistus, 

 Ritz. Bos, A. ritzemabosi, Schwarz, and Heterodera radicocola, Greef., 

 all do much harm and are very difficult to eradicate. All dead, 

 infested plants, as well as the soil round their roots, should be at 

 once burned. A list of insect pests of chr}-santhemums in coimtries 

 other than Great Britain is given and a bibliography of 18 works is 

 appended. 



