238 



one estate, no method of dealing with this pest in the growing crop 

 being known at present. It is recommended that diseased tubers 

 and all trash should be destroyed by burying with lime and that 

 planting should be undertaken on fresh ground. 



The scale, Chiofiaspis dtibia, Mask., was reported as attacking several 

 species of ferns, and the larvae of Prodenia litura, the flowers of 

 begonia, other flowering plants. 



The Agromyzid lantana seed-fly, introduced from Hawaii in 1911, 

 appears to be thoroughly established and to be exercising an inii^ortant 

 check on the troublesome lantana weed. 



Petherbridge (F. E.). The Control of the Apple Capsid Bug by 

 Spraying. — Jl. Bd. Agric, London, xxiv, no. 12, March 1918, 

 pp. 1401-1410, 8 figs. 



The experiments recorded in this paper are a continuation of those 

 carried out during the season of 1916 [see this Review, Ser. A, v, p. 290]. 

 Observations on the amount of damage done by Plesiocoris rugicollis 

 (apple capsid bug) throughout the season showed marked reduction 

 due to spraying. Details of the experiments are given. Soft-soap 

 and nicotine, and soft-soap and pyridine, both proved effective washes 

 against Capsids ; for the former, with soft water 10 lb. of soap per 

 100 gals, or even less is sufficient, but with hard water more may be 

 necessary ; from 7 to 8 oz. of nicotine is required. The best time 

 for spraying varies with the season, but, as a rough guide, about 10 

 davs after the first markings of the leaves by the Capsids the first 

 spray should be given, as then most or all of the bugs will have hatched. 

 The date is usually about a week before blossoming. When two 

 sprays can be given, these should be once before blossoming and 

 once just after blossoming. As eggs are laid in the twigs, care should 

 be taken not to plant nursery stock from an infested area in a non- 

 infested one. 



Lees (A. H.). Nicotine-Paraffin Emulsion. — Jl. Bd. Agric, London, 

 xxiv, no. 12, March 1918, pp. 1411-1415. 



Suggestions for the best contact insecticides for certain sucking 

 insects are given in this paper with a view to reducing the number 

 of spraying operations wherever possible, while labour is so difficult 

 to obtain. In the author's opinion, the most satisfactory spray is a 

 2 per cent, paraffin emulsion. Used alone this emulsion is capable 

 of killing Aphids and many other sucking insects, but is not powerful 

 enough to kill Capsids, caterpillars or beetles. The addition of ^ per 

 cent, of nicotine renders it much more efficacious. The formula is 

 then : — soft soap, 20 lb. ; paraffin, 2 gals. ; nicotine, | lb. ; water, 

 100 gals. The soft soap is first dissolved in 5 to 10 gals, of boiling 

 water. The paraffin is then taken up in a garden syringe with a rose 

 attached and squirted violently into the soap solution, thus obtaining 

 an emulsion. The nicotine is then added and the mixture diluted to 

 100 gals, in all. Capsids are killed when thoroughly wetted by this 

 spray, while larvae of the cabbage white butterfly [Pieris brassicae] 

 remained motionless on the leaves and finally died. Larvae of the 

 gooseberry sawfly [Pteronus ribesii] when hit by the fluid fall to the 



