SUMMARY OF LIFE HISTOEY AND HABITS. 



The boUworm has four distinct stages in its development — namely, 

 the egg, larva, pupa, and adult or moth. 



The eggs are most easily found on the silks of corn, and may be 

 readil}' seen with the unaided eye. The}^ are oval in shape, whitish 

 or yellowish in color, and average in diameter about 0.45 to 0.50 mm. 

 The number of eggs deposited by a single moth varies from about 500 

 to 3,000 with an average of about 1,100. The eggs are laid, begin- 

 ning usually about twilight, on the several food plants of the larvse, 

 which are preferably corn, cotton, tomatoes, etc., in about the order 

 named. Eggs on corn are placed almost promiscuously over the plant, 

 but there is shown a preference for silks when these are present. 

 On cotton, eggs arc placed more largel}" on the leaves and scpiares, 

 but there is a considerable scattering of them over the entire plant. 

 Eggs hatch in from two and one-half to ten daj's, depending on the 

 season. 



In the larval stage, the insect is variously designated as boliworrii, 

 bud- worm, corn ear-worm, tomato-fruit worm, etc., depending on the 

 particular plant and part of the plant infested. It is during this stage 

 onl}' that injury is inflicted. Newly hatched bollworms are very small, 

 and are usually overlooked by planters until they are of sufficient size 

 to attract attention by their injury. The bollworm is a voracious 

 feeder, and during the sunuuer may complete its growth in from 

 twelve to fifteen da3's. During the cool weather of spring and fall 

 the rate of growth is much slower. A full-grown bollworm measures 

 from li to li inches in length. Larvte var\' much in color and mark- 

 ings, ranging, in diflferent individuals, from pale greenish to rose- 

 colored, dark brown, and almost black. 



When full grown the bollworm leaves its food plant and burrows in 

 the soil to a depth, usually, of from 2 to 5 inches, and, after construct- 

 ing a cell extending upward nearly to the surface of the soil, enters 

 the pupal stage. This stage, during summer, lasts from ten days to 

 two weeks, and longer in the spring and fall. The insect hibernates 

 in the pupal condition. 



The bollworm moth, like its larva, varies much in color, ranging 

 from a dull olive green to a pale yellow. The wings expand about 1^ 

 inches, and the body is about I- of an inch in length. During the day 

 the moths hide in grass or weeds around the margins of fields or 

 among the foliage of plants infested by the larva3. Toward dusk they 

 leave their retreats and feed on the nectar of various flowers. In 

 cotton fields their j)rincipal food is the nectar secreted on the squares 

 and flowers of the cotton plants. After feeding oviposition begins, or 

 this process may alternate with feeding. Eggs are deposited almost 



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