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8 lb. or 1 U.S. gal., oil (Corvus or Red Junior), 2 gals., and water, 1 gal. 

 The soap is thoroughly dissolved in the water and the oil then slowly 

 added, the mixture being stirred all the time. The stock solution, 

 about 4 U.S. gals., is diluted 1 to 50, making 200 U.S. gals, of spray 

 for use. This spray is slow to take effect and one application is not 

 sufficient to kill all the scale-insects, but it can be used at any time 

 of year without injury and can be mixed with Bordeaux mixture, 

 soluble sulphur against rust mites, or mth arsenate of lead. Observa- 

 tions on Diatraeo, saccharalis (moth stallv-borer of sugar-cane) have 

 already proved that its abundance varies inversely with the rainfall, 

 and also that infestation is much greater in fields where the trash has 

 been burnt [see this Revieiv, Ser. A, iii, p. 760]. The degree of 

 infestation in various localities is given in tables. D. saccharalis was 

 found to occur in greater abundance during the year under review 

 than in the previous year, in spite of heavier rainfall, the reason being 

 that much cane was planted on new land, and under these conditions 

 is always more heavily infested than when grown for the second year 

 on the same land. The trash should not be burnt in fields to "be 

 ratooned and seed should be selected in the field where it is cut, any 

 borer-infested seed that is discarded being destroyed immediately. 



Flea-beetles infesting tobacco in Porto Rico include Epitrix 

 cucumeris, Harr., E. parvala, F., E.fuscata, Duv., and Systena, basalis, 

 Duv. E. cucumeris is the worst pest, damaging the tobacco crop 

 throughout the year. The eggs are laid in the soil round the roots and 

 hatch in about five days, the young larvae immediately feeding on 

 the roots. The larval stage lasts for 20 to 35 days, the adult beetles 

 emerging about six days after pupation. There are numerous alternate 

 food-plants, many of them growang abundantly near tobacco fields, 

 particularly Solanum torvum (wild egg-plant), S. nigrum and Physalis 

 pubescens. The life-history and habits of E. parvula and E. fuscata 

 are very similar, other food-plants of E. parvula including Cleoms 

 spinosa, Leptilon canadense and Lycopersicum esculentum (tomato). 

 Control measures for all these flea-beetles are identical. Weeds and 

 bushes adjacent to tobacco fields should be cut down. Small patches 

 may be left as traps, to be sprayed with Paris green or destroyed by 

 burning when the tobacco crop is harvested. Old tobacco plants 

 should be pulled up immediately after the harvest, in order to destroy 

 the beetles at the roots. The seed beds and young tobacco plants 

 should be kept dusted with a mixture of 3 per cent. Paris green and 

 97 per cent, corn flour or wood ashes. A spray of 3 or 4 lb. arsenate 

 of lead to 100 U.S. gals, water is efficacious, or the arsenate may be 

 used dry with an equal amount of wood ashes. 



Vegetable pests included the larvae of Xylomeges sunia, Protoparce 

 {PhlegetJiontkis) sexta and Phytometra [Plusia) sp. on tomatoes, egg- 

 plants and peppers. The first-named is controlled by a spray of 

 2h lb. arsenate of lead to 50 U.S. gals, water. The changa [Scapteriscus 

 didactylus] was controlled by surrounding young plants with a ring 

 of mixture composed of 3 per cent. Paris green and 97 per cent, flour 

 rich in gluten. Aphids and lace-bugs on peppers, egg-plant and 

 cucumbers were controlled by a spray of Black-leaf 40, 1 fluid oz. to 

 8 U.S. gals, water containing | lb. whale-oil soap. The Chrysomelid 

 beetle, Cerotoma ruficornis, strips the leaves of beans and cowpeas, 

 while the larvae attack the roots. Methods of control are collecting 



