172 MAINS AGRICULTURAL EXPERIMENT STATION. I904. 



Since the flies are so long on the wing and lay their eggs over 

 such an extended time, the full grown maggots are found at 

 different periods. The first eggs are laid naturally in the early 

 fruit and accordingly as soon as August tenth full grown mag- 

 gots have been recorded in Early Harvests. On the other hand, 

 some of the later maggots, from eggs laid in harder winter 

 varieties, do not acquire their full size until late in the fall or 

 winter. These are the maggots that are stored with the fruit. 



So far as has been observed the maggots are never mature 

 enough to leave the apples before the fruit falls, but the full 

 grown maggots (shown in fig. 31) bore out of the windfalls and 

 bury themselves an inch or less in the ground. Or, if they are 

 in gathered fruit where they cannot find a suitable burying 

 ground, they creep away beneath some protecting object instead. 

 Soon after leaving the apple (sometimes the transformation 

 takes place within the apple but not often) the maggots shrink a 

 little in length and bulge a little in thickness, the skin at the 

 same time growing tougher and slightly darker. 



The insect is known in this form (fig. 32) as the pupa, and 

 rests in this stage all winter. With the return of summer a sec- 

 ond transformation takes place which is complete when a fly 

 (fig. 30) with banded wings breaks out of the tough skin which 

 has covered the pupa all winter and comes from its hiding place 

 to seek an orchard where it may spend its life laying eggs in the 

 pulp of young apples. 



PREVENTATIVE MEASURES. 

 As pointed out here, it is useless to try to poison the growing 

 maggots as they are within and protected by the apple. It is 

 also evident that if the maggots contained in windfalls and 

 picked fruit are destroyed one year there will be no trouble to 

 fear from them the next. Of course it is highly improbable that 

 even by the greatest vigilance, every maggot could be thus 

 destroyed. But when it is considered that each maggot left to 

 its own devices has a chance of becoming a fly capable of laying 

 at least three hundred eggs, and that each maggot undestroyed 

 this year may mean three or four hundred next year, the im- 

 portance of killing as many as possible is evident. If the apple 

 maggots, as do many insects, all developed about the same time, 

 the problem would be much simpler, but as full grown maggots 



