466 THE GYPSY MOTH. 



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

 two weeks. Foliage uninjured. 



5 Ibs. 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 Ibs. 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 Ibs. 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 Ibs. 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 Ibs. 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 Ibs. to 150 gal. 

 of water. Two died the third, two the fourth, 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 Ibs. 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 



