466 



THE GYPSY MOTH. 



dying within a week, and the last one dying in a little over 

 two weeks. Foliage uninjured. 



5 lbs. Arsenate of Lead to 150 gal. Water. 



No. 99. — March 7, 1894. Ten caterpillars, three days 

 old, were placed on lettuce leaves which had been treated 

 with arsenate of lead, in the proportion of 5 lbs. to 150 

 gal. of water. One died the first, two the third, one the 

 fourth, four the fifth, and one died and one was lost the sixth 

 day. 



No. 100. — May 9, 1894. Ten caterpillars, six days old, 

 were placed on lettuce leaves which had been treated with 

 arsenate of lead, in the proportion of 5 lbs. to 150 gal. of 

 water. Four died the third, three the fourth and three the 

 fifth day. 



Check experiment : none dead. 



No. 101. — May 28, 1894. Ten caterpillars, of the first 

 molt, were placed on lettuce leaves which had been treated 

 with arsenate of lead, in the proportion of 5 lbs. to 150 gal. 

 of water. Three died the fourth, one the fifth, four the sixth 

 and two the seventh day. 



Check experiment : none dead. 



No. 102.— June 10, 1894. Ten caterpillars, of the 

 second molt, were placed on lettuce leaves which had been 

 treated with arsenate of lead, in the proportion of 5 lbs. to 

 150 gal. of water. Two died the second, three the fifth, one 

 the sixth, three the seventh and one the ninth day. 



Check experiment : none dead. 



No. 103. — June 21, 1894. Ten caterpillars, of the third 

 molt, were placed on elm leaves which had been treated 

 with arsenate of lead, in the proportion of 5 lbs. to 150 gal. 

 of Waaler. Two died the third, two thcvfourth, one the fifth 

 and five the sixth day. 



Check experiment : none dead. 



No. 104. — June 29, 1894. Ten caterpillars, of the fourth 

 molt, were placed on elm leaves which had been treated with 

 arsenate of lead, in the proportion of 5 lbs. to 150 gal. of 

 water. Three died the second, two the third, two the 

 fourth, one the fifth and two the sixth day. 



Check experiment : one died and two pupated the second 



