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to other plants. On the other hand, the principal native animal food taken was aphids. Guppy (1946) found that earwigs can be kept from cannibalism by providing them with almost any common herbaceous plant although they prefer certain varieties to others.

During experiments at Puyallup, Washington in which 590 possible attractants for earwigs were tested by Crumb, Eide and Bonn (1941), eleven substances consistently attracted most earwigs and all of them were of an oily or greasy nature. From the standpoint of effectiveness and economy, fish oil seemed the most practical attractant to incorporate into poison baits.

The normal number of broods per year is two. One occurs in the early spring and the second sometime in the late spring or early summer (Beall, 1932 and Crumb, 1941). Guppy (1946) reports that in the Northwest a third brood may be produced but only exceptionally.

Hibernation occurs during the cold winter months, but the duration of hibernation and proportion of earwigs hibernating varies with the locality. Observations made in western Washington by Crumb in 1941 indicate that a large percentage of females will appear above the ground after a long rainy spell during their normal hibernation period.

Guppy, in 1946, found that the European earwig must have a very moist habitat for the eggs and young nymphs to survive. Adults that are kept in a dry locality, and. which are not given succulent food, will drink liberally on coming into contact with water.

The European earwig's reluctance for flight was noted by Blathwayt in 1892. Collings, in 1908, states that flight occurs only on rare occasions. On the other hand, evidence that the earwig never flies was given by Verhoeff in 1917. Flight habits were observed by Richter.