THE SUGAR-CANE MOTH BORER. 
51 
Table VIII. — Effect on moth-borer larvw of immersion of infested cane 
cuttings — Continued. 
Solution. 
Expo- 
sure. 
Num- 
ber of 
lar- 
vae. 
Condition of larvae im- 
mediately after treat- 
ment. 
Penetration of solution 
in cane cutting. 
Condition 
of larvae 
two weeks 
after treat- 
ment. 
Nicotine sulphate (40 per 
cent nicotine), 1 part 
to 500 parts water. 
Dip... 
Ihour. 
Dip . . . 
1 hour. 
...do.. 
10 
7 
7 
10 
10 
9 alive, 1 small one dead 
between stalk and leaf 
sheath. 
Probably penetrated the 
stalks. 
do 
4 alive. 
All dead. 
Potassium sulphid, 3 
pounds per gallon 
water. 
All alive 
do.... 
do 
do 
Potassium sulphid 1£ 
All alive, 1 emerged from 
cane and in the solu- 
tion. 
do 
pounds per 10 gallons 
water. 
Soaking the cuttings for 1 hour in either Bordeaux mixture or 
nicotine sulphate solution was found to kill all the larva? within 2 
weeks. Only 1 larva was killed immediately, however, even after 
an immersion of 1 hour. 
Eggs, larvae, and pupae were next subjected to immersions of 1 
minute and 1 hour in the various solutions, with results as shown 
in Table IX. The larvae and pupae had previously been removed 
from the stalks of cane. A cluster of eggs, 5 larvae, or 5 pupae 
were used in each exposure. 
Table IX. — Immersion of eggs, larvw, and pupa? of the moth borer in various 
solutions. 
Solution used and stage of insect. 
Exposure. 
Effect within 2 
days. 
Effect within 10 
days. 
T ,rdeaux mixture: 
Eggs 
Did not kill 
do 
All hatched. 
Larvae 
Do 
.. do 
Pupae 
do 
do 
All emerged. 
Fish-oil soap: 
Eggs 
do 
do 
Larvae 
do 
Do 
do 
Pupae 
do 
.All killed 
Nicotine sulphate (40 per cent nicotine) : 
Eggs 
do 
None hatched 
Did not kill 
do 
. do 
All dead. 
Larvae 
1 minute 
1 hour 
do 
1 dead out of 5. 
Do 
Do. 
Pupae 
All emerged. 
All hatched. 
Potassium sulphid, 3-100: 
Eggs 
do 
. . do 
Larvae 
do 
Do 
do .' 
1 dead out of 5. 
Pupae 
. do 
...do 
All emerged. 
Potassium sulphid, l-J-100: 
Eggs 
.. . do 
do 
All hatched. 
Larvae 
1 minute 
...do..: 
1 dead out of 5. 
Do 
.. . do 
All healthy. 
Pupae 
do.. 
. do 
All emerged. 
Untreated eggs used as a check hatched as usual. Of 5 untreated 
larvae, 1 died within 10 days. All of the 5 untreated pupae were 
alive at the end of 10 days. 
It will be noted that pupae immersed for one hour in fish-oil soap 
solution were killed, while eggs immersed for one hour in nicotine- 
sulphate solution did not hatch. The other solutions were ineffective. 
It is evident that larvae and pupae are more seriously affected by these 
