224 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 4 



demonstrated in laboratory and field experiments. In dipping plants, 

 the solution simply runs off of the aphides and leaves without appar- 

 ently having any caustic or killing effect whatever. If we had added 

 a small amount of soap no doubt the extract would have stuck and done 

 its work. 



A series of plants dipped in solutions of hme-sulphur, 32.5° Beaume, 

 in the proportions of 1 to 40 and 1 to 30 were quite badly burned in 

 every case and only a small per cent of aphides was killed. The 

 tendency of the lime-sulphur to run off the leaves without apparently 

 touching the aphides was almost as marked as in the case of the 

 tobacco extract. 



Spraying in the Field. — ^During the latter part of August we sprayed 

 a very badly infested field of two acres. We used a knapsack 

 sprayer. There were seventy-six rows (all about the same length) 

 of cabbages in the field. We sprayed sixteen rows with Black Leaf 

 extract 1 to 64 and used forty-eight gallons of mixture. The material 

 was very effective; but it did not spread over the leaves readily and 

 more material was necessary for a given area than of the fish-oil soap 

 solution. 



The remaining sixty rows were sprayed with the fish-oil soap solu- 

 tion at the rate of 1 to 6. The results were very encouraging. The 

 material spread readily and killed all aphides hit. We used, on an 

 average,. 2 1-3 gallons to the row. At this rate, it would have cost 

 to spray the two acres by hand, using fish-oil soap and counting cost 

 of material and labor, about $2.15 per acre. In other field experi- 

 ments equally good results were obtained with the proportions of 

 1 to 7. This would sHghtly lower the cost of spraying per acre. 



I believe a cheaper and more effective method of spraying cabbages 

 would be to mount a barrel with two leads of hose in a one-horse 

 wagon and have a man on the ground at the end of each hose to 

 direct the nozzle. 



Whether cabbages can be sprayed with power sprayers effectively 

 or not is a question upon which we need more definite information. 



NOTES ON SOME INSECTS AFFECTING THE SUGAR CANE 



By F. W. Urich, Entomologist, Board of Agriculture, Trinidad 



The sugar cane has been cultivated in Trinidad for a long time and 

 there are localities in which canes have been grown without interrup- 

 tion for quite a century. It, therefore, speaks very well indeed for 

 the vigor and hardiness of canes that today there are not more cane 

 pests to contend with than we have at present. It is true that many 



