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A 4-year study in the virgin organic soils of southwestern Quebec revealed that most elaterid larvae moved from the subsurface to the top 10 in. of soil in early May, when the soil temperature at a depth of 4 in. was approximately 35°F. This upward movement readied its peak when the topsoil moisture content was 200% and the soil temperature at 4 in., 55°F. In early June, when the soil temperature reached 67°F, the larvae began to move downward and very few larvae were found in the first top layers of soil when the temperature was above 72°F. This downward movement lasted until the end of August and again the larvae moved up to feed near the surface of the soil until the first frost, usually recorded in mid-November. The data indicate that June to early September is generally the most favourable period for growing vegetables.

The onion maggot, Hylemya antiqua (Meig), has three distinct generations a year in Canada (Armstrong 1924, Hammond 1924, Baker 1928, Lafrance and Perron 1959), and usually two generations in England (Miles 1955). In Canada the three generations overlap considerably and adults of each generation are observed in flight in late summer (Perron et al. 1953). It is the most important pest of onions (Matthewman et al. 1950, Hudon and Perron 1956), and the first generation is the most injurious to the onion plants (Kendall 1932, Miles 1953).

During the course of investigations on the life history of rvirer.vorms (Coleopteri:Elateridae) in the orfanic soils of Ste Clothilde, Quebec, hand separating of dirt and grass was-found tedious and time-consuming. The pioblem "tur, -"t bv de"signing a special apparatus for collecring ',,ui-r The sieve tray (Fig.2) is connected to a u'ooden bar fixed to the frarne rr ith a hinge. This ba; is held under tension bv a door spring connecting it to the frade and by a chain to the sie\re tray. ihe upper 6na 6f that bar l-ays on a series of doll-'els fixed horizontailv on the vertical rear end of the druni. By rotatinq the drum the shakinq motion on the bar striking on the dowels giuer " vib"ration on the sierre tra-lY. The comb made of n"rrdov steel plates is bolted under the upper frame; the tips of the plates extend to % in. of the surface of the drum, bassing between the rorvs of nails fixed to the latter. The comb keeps the nail-6ov.tid dtu-f-,-ee of debris such as roots.The oscillating steel-studded plate (Fig. z)