Page:The Scientific Monthly vol. 3.djvu/394

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388 THE SCIENTIFIC MONTHLY

and injurious forms^ with the former largely in the majority. The Orthoptera with its 3.28 per cent, of destructive species contain a large majority which feed upon vegetation. While most Lepidopterous larvse feed upon vegetation, yet the fact that many confine their activi- ties to plants not under cultivation by man or occur in small numbers, brings the percentage down to 2.73. The Heteroptera are plant feeders with numerous exceptions; predatory and injurious insects are abun- dant in the Coleoptera and the Diptera contain predaceous and bene- ficial species as well as feeders on animal and vegetable tissue. In these three orders, the percentages of destructive species are similar.

Therefore, the insect losses in the state of New Jersey are due en- tirely to the activities at different times of only 186 species, some of which are and any one of which may become notably abundant.

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