vin] THE LIFE-STORY AND THE SEASONS 99 



in June. The dull greyish larvae feed on many kinds 

 of low-growing plants, usually hiding in the earth by 

 day and wandering along the surface of the ground 

 by night, biting off the farmer's ripening corn, or 

 burrowing into his turnips or potatoes. On account 

 of the burrowing habits of this insect it can feed 

 throughout the winter, except when a hard frost 

 puts a temporary stop to its activity. By April it 

 has become fully grown and pupates in an earthen 

 chamber a few inches below the surface. The Turnip 

 moth in our countries is partially double-brooded, 

 a minority of the autumn caterpillars growing more 

 rapidly than their comrades so that they pupate, 

 and a second brood of moths appear in September. 

 These pair and lay eggs, the resulting caterpillars 

 going as Barrett suggests (1896, vol. in. p. 291) 'to 

 reinforce the great army of wintering larvae.' 



Such underground caterpillars, to a great extent 

 protected from cold, can continue to feed through 

 the winter. With other species we find that the 

 larva becomes fully grown in autumn, yet lives 

 through the winter without further change. This 

 is the case with the Codling moth (Carpocapsa pomo- 

 ndla\ a well-known orchard pest, which in our 

 countries is usually single-brooded. The moth is 

 flying in May and lays her eggs on the shoots or 

 leaves of apple-trees, more rarely on the fruitlets, 

 into which however the caterpillar always bores by 



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