February, ’23] 
BRITTAIN: CABBAGE MAGGOT COFTROL 
67 
Age 
Eggs . 
1 day.... 
2 days 
3 days.... 
7 days... . 
9 days 
14 days... 
17 days... 
Full grown 
Laboratory and Field Tests 
Conditions 
Laboratory 
Field 
Check 
Laboratory 
Field 
Check 
Laboratory 
Field 
Laboratory 
Field 
Laboratory 
Field 
Check 
Laboratory 
Field 
Laboratory 
Field 
Laboratory 
Field 
Laboratory 
Field 
Check 
Percentage killed 
or disappeared. 
100 
100 
25 
100 
100 
20 
100 
100 
100 
100 
95 
100 
30 
85 
80 
15 
40 
25 
45 
20 
15 
Two strengths of HgCl 2 , viz-, 1-1000 and 1-1500, were used on eggs, 
with 100% killed in each case. 
The following are the results from the second lot tested under field 
conditions only. 
Field Tests 
Age Percentage killed or 
Disappeared 
1 day.100 
Check.20 
2 days.100 
Check.40 
3 days.100 
Check.20 
7 days .. 90 
Check. 10 
9 days. 80 
Check. 15 
14 days. 10 
Check. 30 
17 days. 10 
Check. 5 
Full grown. 15 
Check. 10 
