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Life history. — In early seasons, under favorable conditions, tlio flies in Maine begin 

 to eiuerjje about July 1, and earlier in the States farther south. They continue to 

 emerge all summer, and are on the wing in abundance until the middle or last of 

 September and occasionally in October. Early frosts check them. The flies lived 

 three weeks in confinement and will probably live longer in nature. They liegin to 

 deposit their eggs in the early fruit by July 1 or earlier, and egg laying continues 

 while the flies are on the wing — the earlier races of flies affecting the earlier varie- 

 ties and the later races the fall and winter fruit. Each female is capable of lay- 

 ing at least between three and four hundred eggs, which are inserted from time to 

 time one in a place by means of a sharp ovipositor through the skin of the apple. 

 The eggs being successively developed in the ovary of the female, after the manner of 

 the barn-yard fowl, the season of egg laying extends over considerable time. The 

 eggs are vertically inserted into the pulp of the apple, with the end opposite the 

 pedicel, which contains the head of the maggot, pointing toward the core. The 

 eggs are deposited in all parts of the apple, usually upon the cheeks, sparingly near 

 the calyx and stem ends, and more abundantly ui^on the pale or shaded side of 

 the fruit. The time required to deposit the eggs is about one half minute. By 

 means of the sharp ovipositor a characteristic puncture, 0.33 mm. (0.0133 inch) iu 

 diameter, is made through the skin of the apple. These punctures can be de- 

 tected by careful observations with the naked eye, but a pocket lens is necessary 

 to see them well. They appear as brownish specks, and have not been before dis- 

 tinguished from the brownish, rusty spots common on apples. Under tie glass they 

 appear as circular or oblong openings, surrounded by a brownish border, somewhat 

 shrunken by the shriveling of the tissue beneath. They may be numerous on the 

 same apple. The eggs hatch in 4 or 5 days under favorable conditions, and the 

 minute larvae begin at once to work in the pulp of the apple. » * » 



They attain their growth, under favorable circumstances, in 4 or .5 weeks, but their 

 development may be arrested by cold, insufiScient food, hardness of the fruit, etc., for 

 a great length of time. Ordinarily they remain in the fruit but a short time after 

 they mature. * * » 



Fruit picked from the trees may contain larvae, and often stored or marketed fruit 

 is alive with maggots. The exit oiienings are characteristic— irregular holes about 

 2 mm. (0.08 inch) in diameter, surrounded by a brownish border. They look as 

 though the maggots had gnawed a hole for the head and then forced the body 

 through, leaving a lacerated border. They may occur anywhere on the apple, but 

 are more frequently found where the brown larva3 trails show through the skin. 

 They begin to appear in the early apples about the 1st of August, and may be found 

 until frost in windfalls, and in the stored fruit as long as the larvae remain. 



It would seem that the development of the larvie is so nicely timed that thej' are 

 not mature until the fruit is ripe. Their development is slower iu late and hard 

 fruits. A dozen maggots may infest the same apple, though a single one is enough 

 to render it worthless. The maggots have been found in numerous varieties — early 

 and late, sweet, acid, and subacid — extending from early iu July through August, 

 September, October, November, December, January, and February. The larvae 

 usually leave the apples and go into the ground an inch or less and soon change to 

 the pupas state. The pupro are occasionally found within the fruit in windfalls and 

 quite frequently in stored fruit. Sometimes the larvas change on the surface of the 

 ground under decaying fruit. On grass ground they probably change in the debris 

 about grass roots. In the bottom of boxes, bins, and barrels, where infested fruit is 

 stored, pupae may be found in abundance. 



In discussing remedies the author combats the idea that the cutting 

 down of the early varieties of apple-trees would destroy the maggot. 



