. Appendix to the Journals of the Senate and Assembly of the ... session of the Legislature of the State of California. alnumber of insects taken in the trap of1892, from which we condense as fol-lows: Total number of insects taken,12,712; different species, over 290;number of decidedly beneficial insects,1,330; number that are often pests,1,604; number of neutral or rarelyinjurious, 9,778. The percentage ofdecidedly beneficial insects killed nearlyequals that of the species which areoften pests, and the important fact thatone beneficial insect usually killsseveral injurious ones must be consi
. Appendix to the Journals of the Senate and Assembly of the ... session of the Legislature of the State of California. alnumber of insects taken in the trap of1892, from which we condense as fol-lows: Total number of insects taken,12,712; different species, over 290;number of decidedly beneficial insects,1,330; number that are often pests,1,604; number of neutral or rarelyinjurious, 9,778. The percentage ofdecidedly beneficial insects killed nearlyequals that of the species which areoften pests, and the important fact thatone beneficial insect usually killsseveral injurious ones must be considered. Nearly one half of thecaptures were moths, but more than three fourths were not of economicinterest and no codling-moths ivere recognized. Seventy-nine per cent ofthe Crambid moths, 88 per cent of the Noctuid moths, 84 per cent of thelarger moths, and 93 per cent of the May beetles were males, and theseproportions were almost the same in the six trap-lanterns operated in1889. Furthermore, in most cases the females that were killed hadalready laid their eggs, so that their capture would not lessen the future. Trap-lantern used in the CorneUexperiments. 156 REPORT OF STATE BOARD OF HORTICULTURE. crop. It was found that about 80 per cent of the Ichneumon or para-sitic flies were females, the ones most needed in insect warfare. Themale moths were doubtless seeking their mates, and the female Ichneu-mon flies were necessarily more active than the males, as they had tofind caterpillars in which to oviposit. These facts are strong argumentsagainst the efiectiveness of trap-lanterns as destroyers of insect pests. After citing the experiences of Professor Steadman of Missouri, whohad made three different tests of trap-lanterns in three different States;of the late Dr. Riley, who had run a trap-lantern during a wholesummer and failed to catch a single codling-moth; of Professor Loch-head, who had two moth-catchers near apple trees in 1901 and failed totake a single codling-moth; o
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