THE ARMY=WORMS. 



from light yellow to reddish brown and has a double row of 

 white spots on its back; these, its food plants, and its 

 fish-hook resting position will usually identify it. 



This large genus contains two common, 

 wide-spread, destructive cut-worms which 

 are sometimes put in the genus Xylopliasia: devastatrix and 

 arctica (Plate LI). The larvae attack garden and field 

 crops; the adults have dark brown front and light hind 

 wings. The larvae of Hadena turbulenta are sometimes 

 noticed on green briar (Smilax) because of their gregarious 

 habits. 



The Fall Army-worm (Plate LI) appears 



Laphygma later than the true Army-worm (Leucania 



frugiperda . \ijii 



umpuncta) and the larvae are not so choice 



about their food for they eat almost any crop, scattering 

 more than do the Army-worms. The pitch-black stripe 

 along each side and the four black spots on the back of 

 each segment distinguish this "worm" from Leucania. 

 The naked pupae hibernate about half an inch below ground. 

 Adults emerge in the spring and the female covers her 

 egg-clusters, placed on grass, with hairs from her own 

 body. There are two or three generations a year but the 

 larvae which appear in late summer are the most destruc- 

 tive. The adult has a "general yellowish, ash-gray color, 

 with the second pair of wings almost transparent, but 

 with a purplish reflection." In the West there is a related 

 species, L. cxigua (Plate LI), which is called the Beet 

 Army Worm because of its ravages among the sugar-beets. 



The Army- worm (Plate LII), which is 



Leucania given the generic name Hcliopliila by some 



umpuncta . . . 



authors, is interesting for several reasons; 



for one, it is a conspicuous example of a species which 

 occasionally gets ahead of its insect parasites and other 

 ills, increasing its numbers to such an extent that its larvae 

 eat all the available food, chiefly grasses, in a given place 

 and are forced to move en masse. However, fate is not 

 to be permanently outdone and soon there comes a time 

 when the species is relatively rare; and then again the 



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