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long, with well fringed wings. She deposits very small pearly white 

 eggs, on the tubers when exposed, either before or after digging, 

 or when stored in the bins or sacks, the larva entering about 

 the eyes or in wounds. They also hatch and enter the growing 

 stalks at the base of the leaves. The larva are about one- 

 twenty-fifth of an inch long, white, transparent, with black heads, 

 and they grow to the length of three-quarters of an inch, when their 

 heads and adjoining parts of the body are brown, shading towards 

 the rear to cloudy white or pink. When hatched, the worm at once 

 enters the potato and lives there just under the skin as a rule, but 

 also boring through any part of it, for about six weeks, when it 

 comes out to pupate, at the mouth of the burrow, in a skin depres- 

 sion, or any sheltered place in the vicinity. Often they lodge in the 

 sacking in which potatoes are stored, and the moth appears in two 

 or three weeks. If the eggs are layed on the stalks of growing 

 plants, the larva bore into the stalk and work down just under the 

 skin into the ground, where they leave the stalk and enter the tubers, 

 sometimes working some distance through the soil to find them. 

 The affected stalks show the burrow plainly under the skin, as its 

 contents are nearly black, and the stalk soon wilts. 



In an infested field, these wilting stalks should be looked for and 

 cut out and burned or submerged in water as soon as possible, as 

 the worms may thus be prevented from entering the tubers. All 

 growing potatoes should be kept well covered with soil by hilling 

 up well, which will require rows to be forty inches apart, and the 

 land should not be cloddy or opened by cracks to allow the moths 

 to get to the tubers and deposit eggs on them. No potatoes should 

 be left in the field, especially at night, unless in tightly tied sacks, 

 and then the same sacks should not be used for storing them, as the 

 moths are sure to deposit eggs on them if any are about. The 

 tubers should not be covered with green vines as the vines are very 

 apt to contain worms, and it is often best to cut and destroy vines 

 before digging the tubers. After digging, the tops and weeds, 

 especially nightshade, should be at once cleaned off the land and 

 destroyed. Weeds and nightshade on adjoining land should also 

 be destroyed. 



When the potatoes are to be stored, if their infestation is sus- 

 pected, soak them for 36 hours in as cold water as is obtainable. 

 This thoroughly destroys the worms and will not injure the po- 

 tatoes if the water is below 60. 



If the worm shows after the potatoes are stored, make the storage 



