Erucivorous: a feeder on caterpillars; said of parasites.
Erythrinus: red; nearly arterial blood-red: carmine, a little diluted.
Erythrinus: deep brick-red, tending to blood-red [vermilion with a little Indian red].
Escutcheon: the scutellum in Coleoptera.
Essential character: see specific character.
Ethology: see ecology.
Eucephalous: with a well-developed head, bearing the normal appendages: applied to certain dipterous larvae.
Eucone: a compound eye in which the individual ocelli have crystalline cones see acone.
Euorthoptera: the Orthoptera excluding the Dermaptera.
Euplexoptera: with beautifully folded wings: an ordinal term applied to the ear-wigs.