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numerous flies are present, the flies on one-half of the grill can be counted and that total multiplied by two for the grill count that is recorded, or one-fourth can be counted and the total multiplied by four for the recorded count. Only one grill count is recorded for each grill placement Dation. If the number of flies landing ont he grill slats after placement do not visible seem to reflect the.actual numbers observed, or if the counting process is delaved and the flies move off of the grill and back to the attractaxit, the grill can be lifted two to three inches and allowed to fall back before making the count. A suggested site record form for each fly grill survey is attached to this manual. The kinds of flies present on the grill should be visually identified and the different kinds counted and recorded separately. This will be dependent upon the ability of the inspector to make rapid visual identifications and should improve with experience. The kinds of flies listed on the survey record form are species or groups of species which are commonly found in landfills and which can be recognized by an experienced person. However, the inspector can amend the kinds or groupings which are individually counted to suit his or her ability to make the visual identifications. For example, the inexperienced person may group the counts into such categories as "blue flies," "small yellow flies," etc., when necessary. The actual fly species composition obtained by methods described in the section which follows can then be used to judge the actual kinds of flies which were present when the count was made. As subsequent surveys are made and compared with the ies composition data, the inspector will become more familiar with the species of flies o=urring at a specific landfill, and the "kind of fly" categories on the record form can be amended accordingly. Until the flies present at a site are easily recognized by the inspector, it is recommended that a sample for fly species composition be obtained during each fly grill survey and taken to the laboratory for identification. Flv Soeci omosifign A monthly collection of flies for laboratory identification of species is required to verify the visual identifications made during grill counts. Accurate identification will provide clues to the sources of any problem species for ascertaining appropriate corrective measures. Netting of flies present on the attractants chosen for grill counts after the count are taken is recommended as the simplest and least time-consuming method for obtaining a representative sample of the lands present. A standard insect aerial net with 15- to 18-inch ring diameter is recommended. To capture flies on amractants surrounded by obstacles, the net is held in one hand so that the net rim (opening) is parallel to the ground, and the net is extended vertically in a cone shape by grasping the net tip with the other hand. The extended net is moved slowly into position about 12 to 24 inches directly above the attractant and then dropped rapidly utilizing both hands simultaneously until the net rim touches the attractant (or if the attractant is wet, the movement is stopped about one- half inch above the attractant surface). The extended net is vibrated and the disturbed flies will fly up into the net tip area. The net is then pulled up above any obstacles using both hands, the tip is released, and the net is swung rapidly from side to side so that the flies are forced into the