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Oniipn

onion, fly, onions, maggot, garden, size, eggs, natural and ground

ONIIPN. AIMum cepa. .The onion is one of the oldeq cultivated as it is one of the most celebrated of ancient vegetables. In Egypt, it attained great excellence and mildness, probably from the steady heat, and constant moisture of irrigation in connection with the rich alluvial soil of the Nile. The Israelites in their wander ings in the desert, lamented the ,loas of onions as one of their privations. Of the Egyptians and their worship of the allium tribe, Juvenal wrote: Now Egypt, mad with superstition grown, Makes gods of monsters, but too well is known, 'Tis mortal sin an onion to devour, Each clove of garlic has a sacred power.

Religious nation. surel and blest abodes, Where ev'ry garden is o'errun with gods' The oniOn is cultivated extensively in every civilized country, and forms a considerable article of transport from one place to another.

European fiy, and also a native species, which seem to have multiplied rapidly from some unknown cause. A minute Thrip, Limothrips tritica has also made its appearance. The cut, Fig. 1, shows the insect in its several stages, magnified, the hair lines showing the natural size. The figures al, b, show larvte; a, male; b, female, and the figure at the right shows the antenna very highly magnified, as will be readily understood, when we recollect that the adult is less than an eighth of an inch in diameter; e, per fect insect. Of the onion fiy, there are two species, -the Native Onion Fly and maggot, (Orta Ara) shown at Fig. 2, enlarged, the hair line natural size. Fig. 3 shows the European Onion Worm, (Antkonlyia ceparum), imported into the United States over forty years ago; natural size; b, maggot, and c, the fly magnified, the hair lines giving the natural size. The report on the Rocky Mountain Locust, and other injurious insects, for 1877, describes both species. The fol lowing is partly taken from the reports of Dr. Fitch, New York. Speaking of the imported fly, we find that in June, as soon as the young seed ling-onions are only an inch or two in height, these insects commence their depreciations and continue them through the whole season, getting their growth and coming out in their perfect state one after another, whereby some of the flies are liable to be always present in the garden, in readiness to deposit their eggs; and maggots of widely different sizes are commonly met with in the same onion. The eggs or fly-blows are loosely plaeed upon the onion slightly above the surface of the ground, some being dropped along the thin edge of the sheath or white membraneous collar, which is formed by the base of the lower leaf elasping around the stalk, and others are crowded into the crevices between the bases of the leaves, slightly above where they issue from this sheath. From two to six or more eggs are usually placed on partic ular plants here and there through the bed.

They are perceptible to the eye, being white and smooth, four-hundredths of an inch (0.04) long,

and a fourth as thick and of an oval form. k% hen the minute tnaggot hatches from the egg, it works its way downward inside of the sheath, its track being marked by a slender discolored streak, till it reaches the root, on which it feeds till it is wholly consumed, only the thin outer skin remaining. After eating the bulb of one plant they attack the next, until sometimes a third or a half of the bed is destroyed. The maggot attains its growth, in summer, in about a fortnight, and changes to a pupa either in the cavity in the onion, or in the wet, slimy earth which is in contact with the onion. It here ceases to move, it becomes contracted and shorter in length, its skin hardens and changes to a tarnished yellow and finally to a ehestnut color with a stain of black at eaeh end. This is the pupa-ease, and the true pupa is inside. In this condition it lies about two weeks before the fly escapes. As a preventive measure worth trial the seed should be sown two inches deeper than usual, so that the 7 can not so readily get to it to lay its eggs. ow also on ground on which straw has been previously burned Rota. tion of crops is also a most important prevent ive measure. When the roots are infested pour boiling water along the drills near the roots, or even on the plants, going over the bed four times during one season. The diseased onions should be pulled. up and burned. Fitch recommends cultivating the onions in hills, scattered among the other vegetables in the garden. With only three or four seedlings in a hill it is evident that the young worms could nowhere find a suffi cient amount of f'ood to nourish them to maturity. Having consumed all the young plants in one hill, they will be unable to work their way through the ground to come at another hill except it be by the merest chance, and will thus perish. The Black Onion Fly was first found to be destructive to onions in Illinois by Dr. Henry Shimer, who writes as follows regarding it . In the latter part of June I first observed the larva or maggot among the onions here; the top dead, tuber rotten, and the maggots in the decayed sub stance. From them I bred the fly. They passed about two weeks in the pupa state. At that time I first observed the flies in the garden, and now few are to be found. Their favorite roosting place is ill a row of asparagus running along the onion-ground, where they are easily captured and destroyed, from daylight to sunrise, while it is cool and wet. During the day they are scattered over the ground and on the leaves and stalks of the onions, and not easily captured. Their wings point obliquely backward, outward, and upward, with an irregular jerking, fan-like movement; flight not very rapid or prolonged. All that I observed originated in one part of the bed, where they were doubtless deposited by one parent fly. Two broods appear in a season