ORCHARD INJURY BY HICKORY TIGER-MOTH. 11 



Feeding injury is seldom conspicuous and usually unnoticed until 

 the third or fourth instar is reached when the larvae become very 

 voracious. Larvae in the first stage are surface feeders. Those on 

 walnut and pear feed on the underside, eating nearly to the up- 

 per epidermis. Those on apple and quince feed on the surface. 

 On these food plants the larvae eat the leaf tissue as they go, while 

 larvae on cherry and oak leave patches of surface uneaten and also 

 may feed on either upper or lower surface of the leaf. Larvae in the 

 second stage feeding on walnut and in the third stage on pomaceous 

 fruits feed at the edge of the leaf, eating everything except the 

 thicker leaf veins. 



The cocoon is spun among leaves or in protected situations on the 

 ground. If the infested trees are in the neighborhood of buildings 

 cocoons may be found under boards, behind doors, or in similar 

 situations. 



THE PUPA, 



The pupa hibernates on the ground. Moisture is probably neces- 

 sary for successful hibernation, for from 36 cocoons wintered out 

 of doors in a screen basket 25 moths emerged, whereas from 21 

 cocoons wintered in the insectary in a battery jar and protected from 

 snow and rain, but exposed to the same temperature conditions, none 

 emerged. 



THE MOTH. 



In emerging the moth usually breaks the pupal skin and then 

 forces its way out of the end of the cocoon. If the cocoon is very 

 loosely constructed the pupa may break out of it before eclosion, but 

 this is not usual. 



Copulation has been noted as early as the day of emergence and 

 oviposition as early as 3 days thereafter. One moth continued ovi- 

 positing for 2 days, day and night, apparently without interruption, 

 adding eggs to the same egg mass. Oviposition is performed de- 

 liberately. The moth's wings are folded back at rest at this time. 



Moths oviposit readily in cages without being fed. They seem 

 to prefer to oviposit on Japanese walnut leaves but will place eggs 

 on cheesecloth or on the sides of the cage. The moths are very 

 sluggish and can be handled easily in cages. 



PARASITES. 



This insect is remarkably free from parasitic enemies. None has 

 been reared by the writer, and as far as he is aware only one species, 

 Pimpla pedalis Cress (18), has been recorded. 



