30 maine agricultural experiment station. 



Saddled Prominent. 

 Heterocampa guttivitta (Walker). 



This species is well known in Maine because it has been 

 excessively destructive to orchard and forest trees during some 

 seasons. The full grown caterpillar is about i^ inches long; 

 body green usually, with reddish brown markings on the back, 

 smooth and hairless (fig. n). The mature insect is a moth 

 expanding about 2 inches, ground color olive-greenish ashen 

 with cream white patches and black markings (figs. 12, 13). 



For Maine the saddled prominent has but one brood. The 

 moths emerge in greatest numbers late in May and early in 

 June. Oviposition begins soon after mating which occurs the 

 first night after emergence. The eggs hatch in about 9 days 

 and the larvae become full grown in 5 weeks (or more accord- 

 ing to weather conditions and food supply). During this time 

 they molt four times. The full grown larvae enter the ground 

 for pupation. In Maine pupation takes place from mid July to 

 late August, the majority of larvae burying late in July. They 

 pass the winter in the pupal stage, under the leaf mold, and the 

 moths emerge in the spring. 



The eggs are deposited singly by the female which in cap- 

 tivity applies the eggs to both sides of the leaf. From the rea- 

 son that the tops of the trees are stripped first and then the 

 lower branches it is to be concluded that the moths by prefer- 

 "ence deposit the eggs upon the upper leaves. Perhaps the same 

 tendency to fly high may account in part for the fact that the 

 hillside forests are in general more largely attacked than the 

 lowlands. 



The full grown larva drops or climbs to the ground and con- 

 structs a cell in the earth or under the leaves at a distance of 

 1 to 3 inches below the surface. This cell is oval and is lined 

 by a thin spinning of silk. 



The insect after remaining in the pupal stage all winter 

 emerges with the warm spring days. 



