220 THE PEANUT— THE UNPREDICTABLE LEGUME 



either harpe and attached to it near the anal angle; clavus button- shaped ; juxta 

 composed of a chitinized plate in front of aedoeagus attached to articulation of harpes 

 by two stout muscles ; ampulla consists of a flap covered with numerous short spines ; 

 editum is slender, spiny at tip ; peniculus oar-shaped ; cornutii composed of 3 groups 

 of several short spines each. 



Female. Much more fuscous brown, the costal area and veins irrorated with grey, 

 the lines less distinct; the orbicular and reniform with slight whitish annuli, the 

 former without pale bar beyond it and no white streak at lower angle of cell, the 

 whitish fascia from apex obsolete. 



Biology. Adults of the fall armyworm are active during the night and 

 in the late afternoon and early morning. The female deposits eggs in 

 masses on grasses, peanuts or other suitable host plants. The number of 

 eggs per mass is reported ( 146) as varying from 9 to 349, with an aver- 

 age of 143 eggs per mass. One female lays an average of about 1,000 eggs. 



The eggs of the fall armyworm hatch in approximately 3 days and the 

 young larvae feed at first on the surface of the leaves, skeletalizing them. 

 Later they devour the leaves of the plant. The caterpillars feed both in 

 the daytime and at night. Occasionally they may be found hiding under 

 clods at the base of plants, but this habit is not nearly so pronounced as in 

 cutworms. When food becomes scarce, the caterpillars may migrate in 

 large numbers seeking additional food plants. Most crops in the path 

 of the march may be destroyed by this pest. At maturity the caterpillars 

 enter the soil and pupate. 



The life cycle, egg to adult, may be completed in approximately 30 

 days. The winter may be passed in the adult stage in the southern part of 

 the insect's range. Part of the winter may be passed also in the larval 

 stage ( 146) . Apparently, this species is not able to over-winter success- 

 fully except in tropical and semi-tropical areas. During the warm months 

 the adults migrate northward and may cause damage by fall in central 

 and northern States. 



Control. Natural enemies are important in the control of fall army- 

 worm. Tachinid flies, hymenopterous parasites, and ground beetles are 

 important enemies of the insect. Vickery (146) lists one species of 

 Hymenoptera ovipositing in the egg of the fall armyworm and 8 species 

 in the larvae. Two species of Diptera and one fungus, Beauveria 

 globulifera, are also listed as parasites of larvae. The fiery hunter, 

 Calosoma calidum (F.), and other ground beetles are listed as important 

 predaceous enemies of fall armyworm (27). The more important 

 insect enemies are as follows : Chelonus texanus Cresson, Apanteles 

 marginiventris Cresson, Meteorus laphygmae Viereck, Zele melleus 

 (Cresson), Sagaritis dubitatus (Cresson), Neopristomerus appalachianus 



