22 
likewise been attacked. The rose leaves were not injured. When 
rose blooms and peach leaves together were offered the im¬ 
prisoned beetles, they fed freely on both. 
Again, May 23, curculios were confined with both bush honey¬ 
suckles and snowballs in blossom. The next day the honey¬ 
suckle blossoms were eaten, and on the second day those of the 
snowball also. On the other hand, beetles shut up with peach 
leaves and peony flowers ate the peach at once, as usual, but 
refused the peony entirely, not having eaten it at all after ten 
davs. 
t/ 
INSECTICIDE EXPERIMENTS. 
My first experiments with insecticides for the curculio alone 
were made July 6, 1888. Two lots were placed under glass 
with leaves and green fruit of the plum, the food of one being 
spraved with Paris green, 1 pound to 50 gallons of water, and 
the other not. The first beetle died in the poisoned lot July 9, 
and the next day all were dead, the check lot continuing with¬ 
out loss. July 28 a similar experiment was made with Paris 
green, 1 pound to 100 gallons, applied until the leaves began 
to drip. The poisoned beetles commenced to die the next day, 
and five of the six were dead on the 31st. In the check lot of 
six, on the other hand, only one was dead. 
An experiment begun with 1 pound to 200 gallons was un¬ 
avoidably suspended two days after, before results were reached. 
Next, April 19, 1889, a lot of curculios, greatly exhausted by 
long confinement in transit, were divided into five lots—the first, 
of twenty-four, a check; the second and third of twelve each; 
the fourth of nine; and the fifth of twelve. The food of the 
second lot was treated with Paris green mixed with water at 
the rate of L pound to 100 gallons; that of the third, with a 
pound to 200 gallons; the fourth, a pound to 300; and the 
fifth, a pound to 500 gallons. 
The previous hardships of the check lot caused many of them 
to die, most of them having been insensible, in fact, when first 
released; but the effects of the poison were nevertheless evident, 
as shown by the subjoined table: 
Paris green experiment No. 1, Apr. 19 , 1889. 
Check lot. 1 lb. to 100gals. 
1 lb. to 200 gals. 
1 lb. to 300 gals. 
1 lb. to 500 gals 
Died. 
Number used, 
24. 
Number used, 
12 . 
Number used, 
12 . 
Number used, 
9. 
Number used 
12 . 
April 22. 
23. 
24. 
25. 
20 . 
27. 
29. 
Total. 
2 
1 
3 
2 
2 
10 
3 
2 
2 
•> 
1 
2 
12 
3 
4 
2 
12 
1 
2 
2 
2 
3 
1 
3 
1 
1 
1 
12 
