HEART AND DART BIOTH. 203 



" I have tried the soft-soap and kerosine on the Dart Moth 

 caterpilhir, and found that when it touched them it killed 

 them. I put some on to a clear piece of ground, poured a 

 little on them, covered them over "with earth, and in a couple 

 of hours uncovered them : they were dead. Others I put in 

 a similar place, covered them over with earth, and watered 

 them with the preparation, but it had not soaked through 

 enough, and they were none the worse. 



** I also poured some round several plants. In a very few 

 cases the grubs had worked up, and were lying dead, but in 

 the majority of cases it had not affected them. The experi- 

 ment was further tried by sending a worker with the mixture 

 in a pail, with instructions to give a small quantity to each 

 plant, but the result showed that the plan would not work for 

 field use. 



"As the caterpillars do not always lie close to the roots, I 

 found that the application of soft-soap and kerosine oil was 

 not of much use. Those which it touched did die certainly, 

 but when we began to scrape away the earth we found many, 

 several inches away, quite unaffected." 



Dry applications such as quicklime, put directly on the 

 caterpillars, also direct applications of soot, sulphur, and salt, 

 failed to have any injurious ei^'ect at all on them ; but still, in 

 the case of soot at least, this would do good by encouraging 

 the growth when only a part of the roots had been hurt, and 

 it would be very likely to keep the caterpillar from coming up 

 through it to attack the plant. Where Cabbages have been 

 attacked by surface caterpillars, the treatment of applying a 

 handful of soot round the stem of each of the plants and 

 earthing them up immediately has saved the crop, and been 

 followed by a good growth. 



In the case of salt also, although it did not kill the grub as 

 a direct application, yet amongst several reports on surface 

 caterpillar-presence, sent me from the north of Suffolk in 

 1884, the following occurred : — 



" Sowed a considerable quantity of salt and then applied 

 farmyard manure to a piece of land, and after ploughing in 

 sowed White Turnips : this was on light land. Eesult, — a 

 first-rate crop." 



In this case the date of application might have something 

 to do with success (a crop sown after a heavy farmyard 

 manuring alone was a total failure) ; but if it chanced the 

 salt above-mentioned was given just when the caterpillars 

 were making their cells, and consequently unable to escape 

 from its influence, this might account for the serviceableness. 



Gas-lime in contact with the grubs was found to kill them, 

 and another observer noted, " They do not like gas-lime." It 



