432 THE GYPSY MOTH. 



molt, were placed on elm leaves which had been sprayed 

 with Paris green in the proportion of 3 lbs. to 150 gal. of 

 w^ater. One died and one pupated the third day ; one 

 pupated the fourth and one the fifth day ; one pupated and 

 one died the sixth day ; one died the seventh, two the ninth 

 and one the fourteenth day. 



Check experiment : three pupated the fourth day, one 

 pupated and one died the sixth day ; one pupated and one 

 died the ninth day ; three died the fourteenth day. 



No. 68 (field experiment). — July 7, 1894. Ten cater- 

 pillars, of the fifth molt, were placed on willow branches 

 which had been sprayed with Paris green, in the proportion 

 of 3 lbs. to 150 gal. of water. One died the third, one 

 the fourth and one the fifth day ; one pupated the sixth, one 

 the fifteenth, one the eighteenth, one the twenty-first, one the 

 twenty-fourth, one the twenty-eighth and one the thirty- 

 first day. Foliage badly burned. 



4 lbs. Paris Oreen to 150 gal. Water. 



No. 69.— April 26, 1894. Ten caterpillars, three days 

 old, were placed on lettuce leaves which had been treated 

 with Paris green, in the proportion of 4 lbs. to 150 gal. of 

 water. Five died the second and four the third day ; and 

 one escaped. 



Check experiment : none dead. 



No. 70. — May 9, 1894. Ten caterpillars, six days old, 

 were placed on lettuce leaves which had been treated with 

 Paris green, in the proportion of 4 lbs. to 150 gal. of water. 

 Two died the second, five the third, one the fourth and one 

 the fifth day ; and one escaped. 



Check experiment : two died the fourth day. 



No. 71. — May 28, 1895. Ten caterpillars, of the first 

 molt, were placed on lettuce leaves which had been treated 

 with Paris green, in the proportion of 4 lbs. to 150 gal. of 

 water. One died the fourth, two the fifth and seven the 

 sixth day. 



Check experiment : one died the fifth day. 



No. 72. — June 10, 1894. Ten caterpillars, of the 

 second molt, were placed on elm leaves which had been 



