.Enemies 197 



FIG. LI. Macronoctua onusta* 



length, shortly after it appears depositing them, scat- 

 teringly, several inches above the ground, some in 

 cracks in the base of old leaves, but most of them 

 between the edges of the overlapping leaves, near the 

 base. 



The eggs, probably all of them, remain unhatched 

 until spring hatching soon after the Iris resumes 

 growth, about the last week in May. The larva 

 begins to feed a little where hatched, and then works 

 down, eating the tender part of the plant, until it 

 reaches the rhizome, and there, or in a contiguous one 

 if it has exhausted the first one, it continues its de- 

 structive work by eating, until it completes its larval 

 development, which usually occurs about August. By 

 this time it is a large caterpillar from one and a half 

 to two inches in length and from a quarter to half 

 an inch or more in diameter; body smooth, cylindrical, 

 of a pale flesh color, sometimes of a yellowish cast, 

 with lateral black spots; head a rich chestnut-red, 

 shiny, rounded and flattened in front. The accompany- 

 ing illustration (Fig. LII) is natural size of the speci- 



*Courtesy of Dr. E. P. Felt. 



