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	1964	Journal of the Lepidopterists' Society	79
	A WEATHER-RESISTANT LIGHT TRAP FOR THE COLLECTION OF LEPIDOPTERA by I. F. B. Common and M. S. Upton Div. of Entomology, CSIRO, Canberra City, A.C.T., AUSTRALIA During the warmer months of the year, light-trapping of Lepidoptera in Australia often yields specimens of indifferent quality, owing to the damage caused by scarabaeid beetles and other hard-bodied insects. To overcome this problem and to collect especially the smaller slow-flying Lepidoptera, Common (1959) designed a transparent light trap for field use. Portable traps of this design are giving very satisfactory results. However, the plastics used for the construction of this trap gradually deteriorate if exposed for long periods to sunlight, making it unsatisfactory as a fixed trap for the continuous sampling of the fauna in any one situation. A light trap has therefore been designed to incor­porate the useful features of the transparent trap, and yet be resistant to strong sunlight and other weathering agents. This; trap has now been in use at Canberra for about three years and has yielded catches of con­sistently high quality. Two features of the transparent light trap were shown to be of special significance. First, the whole area surrounding the trap was illuminated, resulting in the exclusion of a large proportion of the scarabs which were attracted to the light source. The catches of Microlepidoptera were also slightly, although not significantly, increased. Second, most of the scarabs which entered the trap were segregated from most of the remainder of the catch, greatly reducing physical damage to the Lepidoptera. To retain these features the fixed trap has been set in a cylindrical pit so that the light source is slightly above ground level, while the funnel beneath the light source leads to a cylindrical celluloid killing chamber incorporating two sorting devices similar to that used in the transparent trap. Description of the Fixed Trap The trap (Fig. 1) is established on a fairly elevated site with a gentle slope, about 30 yards from a gully. A concrete-lined pit (A), 3^2 feet in depth and 2 feet in diameter is set in the centre of a low mound about 28 feet in diameter and about VA feet in elevation. The pit is surrounded at ground level by a 9 inch strip of concrete (B). The trap (Fig. 1) is lowered into the pit so that the centre of the 250 watt high pressure mercury vapour discharge lamp (C), used as the light source, is about 3 inches above the slope of the mound. The upper edge of the stainless steel funnel (D), beneath the lamp, is supported by a broad truncated cone of stainless steel (E), ending in a ^ inch vertical rim (F), which rests on the concrete surrounding the pit top (B). Radiating from the

	80                                       Common and Upton: Light trap                     Vol.18: no.2 lamp above the funnel are four vertical stainless steel vanes (G), and above these a convex glass window pane (H), two feet in diameter, is supported by four vertical rods to protect the lamp and the trap from rain. Any rain which does enter the trap during windy periods is drained through the centre of the killing chamber (J) to the bottom of the pit and thence out through an agricultural drain to the nearby gully. Three legs (I) are fixed beneath the funnel so that the trap, when removed from the pit, can be stood upright. They also act as guides when lowering the trap into the pit.
	Fig. 1. Vertical section of the fixed light trap.

	1964	Journal of the Lepidopterists' Society	81
	The cylindrical killing chamber (J) (Fig. 2), 18 inches in diameter and 18 inches deep, is made of celluloid with a close-fitting lid, through which passes the lower opening of the funnel (D). This opening is arranged so that all insects reaching the chamber from the funnel are directed against a vertical baffle (K) to the central section of the upper tray (L). The actively flying insects disperse in this portion of the chamber and most die in the outer sections of the tray. The scarabs crawl around within the central section and drop down through one of two holes (M), about 7A inch in diameter, on to two inwardly sloping baffles and thence to the central section of the tray beneath (N). Here the procedure is repeated, those actively flying insects which have fortuitously entered the second portion of the chamber tending to die in the outer sections of the second tray (N), while the scarabs once again find their way through similar holes (O) in the central section to the lowest portion of the chamber. Thus most of the scarabs accumulate in the lowest portion of the killing chamber, while the softer-bodied insects are distributed over the upper and middle trays. These trays are removed for sorting the catches. Near the centre of each tray, beneath the opening of the funnel, small convex areas of plastic gauze (P) allow rain water to pass through the two trays to a similar gauzed opening in the bottom of the killing chamber. A small tin with perforated lid (Q), as described by Robinson (1952), is used in each of the three sections of the killing chamber for the killing agent, tetrachloroethane. In assembling the trap, the killing chamber is first suspended on wires (R) from three points within the pit. The trap funnel is then lowered gently into the pit so that its lower opening enters the top of the killing chamber, sealing itself with a rubber gasket (S). Centring of the trap in the pit is assisted by the three legs. The removal of the trap from the top of the pit is facilitated by two hand-grips attached to the outer edges of the vanes on each side of the lamp. The electric cable to the trap reaches the pit underground from a nearby power source. The removal of the killing chamber from the pit is effected by a three-hooked handle inserted in the suspension loops (T). Discussion As in the transparent trap, the design of this trap permits the whole of the area surrounding it to be illuminated. Scarab beetles which land on the ground near the transparent trap are prevented from entering by its smooth sloping sides. In the present fixed trap, a similar function is performed by the sloping sides of the truncated cone (E) and the vertical rim (F). Large numbers of scarabs collect and remain more or less immobile at the outer edge of this slope.

	Common and Upton: Light trap	Vol.18: no.2
	Fig. 2. Exploded view of the killing chamber of the fixed light trap.

	1964	Journal of the Lepidopterists' Society	83
	The performance of a fixed trap cannot be compared quantitatively with other traps. However, there is little doubt that the Lepidoptera catches are comparable with those that might be expected in an opaque trap, using the same light source. The catches of Scarabaeidae have been consistently low, even in the middle of their flight periods and, as most are segregated from the catches of Lepidoptera. the quality of the latter has remained high. The size of the killing chamber and the ample floor area of the trays tend to prevent further damage to specimens which fly actively before death. An unexpected feature of this trap is that it collects a variety of terrestrial arthropods, including apterous and brachypterous insects, which are not normally taken in light traps. These include the first known specimens of certain brachypterous Oecophoridae, as well as caterpillars, centipedes, scorpions and spiders. Even small lizards have occasionally been taken. Acknowledgements Thanks are due to Mr. S. Jackson, who constructed the trap, and to Mr. L. A. Marchall who prepared the line drawings. References Common, I. F. B., 1959. A transparent light trap for the field collection of Lepidoptera. Journ. Lepid. soc. 13: 57-61. Robinson, H. S., 1952. The use of anaesthetics in funnel mercury vapour insect traps. Entomologist 85: 97-101. Div. of Entomology, CSIRO, P.O. Box 109, Canberra City, A. C. T., AUSTRALIA
	A RANGE EXTENSION TO MISSOURI FOR MONODES GEORGEI (NOCTUIDAE) During the first and second weeks of May 1962 I collected at black light a series of noetuid moths which were later identified as Monodes georgei Moore & Rawson by Dr. A. E. Brower. The range of this rather recently described species is given as Quebec, Nova Scotia and Living­stone Co. Michigan (Forbes, Lepid. N. Y. and neighboring states, part 3; 1954). Specimens were collected at several points through the Missouri Ozarks from Oseola in St. Clair County to Warsaw in Benton County. The species is an apparent native of the Ozark fauna as the flight time is a full month ahead of the northern population making a migration from that area impossible. These records extend the known range of georgei to the lower edge of the Upper Austral Zone. Whether the species exists as a relict form on the Ozark Plateau is an interesting question. To date I have been unable to learn of any records from the intervening area. Richard Heitzman, 3112 Harris Avenue., Independence, Mo., U. S. A.