533 



row. A wide angle mist nozzle is attached in the centre of the top of the 

 cylinder directing the spray downward on to the top of the foliage and 

 a similar nozzle is placed on each side of the 8-in. opening halfway 

 between the ends of the cylinder. These nozzles should be adjustable 

 so that the spray may be directed either inward into the row of plants 

 or upward. The ends of the cjdinder are enclosed with an iris 

 curtain so that the aperture can be adjusted to the needs and size of the 

 plants. The nozzles are attached to a common hose, which is connected 

 with the pressure pump and sprayer tank. As the insects cannot escape 

 from the cylinder, the majority of them are killed by direct contact of 

 the spray or the resulting fumes. The apparatus is adaptable and may be 

 used on the smallest plants ; it also ensures maximum efficiency of the 

 material applied. With a power traction sprayer it can be operated by 

 one man, and an acre may be sprayed in an hour. Owing to the dry 

 season six applications were made at intervals of about a week, using 

 a pressure of 200 lb. Nicotine sulphate, 1 : 1,000, and whale-oil soap, 

 1 lb., gave the best results ; Bordeaux mixture, 4-4-50, and nicotine 

 sulphate, 1 : 800, giving the next best. 



Leach (B. R.) & Brinley (F. J.). U.S. Bur. Ent. Experiments with 

 Contact Insecticides for the Control of the Japanese Beetle 



[Popillia japonica). — Jl. Econ. Ent., Geneva, N.Y., xv, no. 4 

 August 1922, pp. 302-305. 



The results of these experiments with various soap solutions indicate 

 that the type of soap is not as important as is the concentration of the 

 spray solution, though certain types of soap are better adapted to this 

 purpose than others. Laundry, resin-fish-oil and fish-oil soaps are not 

 recommended for this purpose. The efficiency of sodium and potassium 

 soaps is in proportion to the concentration of the spray solution. Sodium 

 soy-bean soap, 10 lb. to 50 U.S. gals, water, killed 90 per cent, of the 

 insects in warm weather. The temperature is the limiting factor in the 

 use of this, the best results being obtained when the beetles are exposed 

 to the sun during the heat of the day. A coarse nozzle should be used 

 with sufficient pressure to wet the foliage thoroughly. 



Many other substances were tried alone and in combination with this 

 soap, but the latter is apparently the only active material, and its 

 efficiency is not increased by the addition of others. 



These experiments on Popillia japonica were carried out also with 

 Macrodactylus subspinosus (rose beetle), the results being substantially 

 the same. 



Smith (L. B.). Larval Food Habits of the Japanese Beetle {Popillia 

 japonica, Newm.). — //. Econ. Ent., Geneva, N.Y., xv, no. 4 

 August 1922, pp. 305-310. 



Recent observations show that the larvae oi Popillia japonica feed in 

 the spring and early autumn, chiefly on living plant tissue [cf. R.A.E., 

 A, X, 303]. An analysis of the contents of the fore intestine showed this 

 substance to constitute about 67-33 per cent, by weight of the total 

 material eaten. When the larvae are feeding they occur at depths 

 varying from ^ to 3 in. in the soil. They will attack the roots of many 

 ornamental shrubs and plants, as well as those of maize, beans and toma- 

 tos. Many weeds and coarse-rooted grasses do not show any appreciable 

 effects from the attacks of the larvae, but the finer-rooted species such 



