Flightless
insects with ectognathous mouth parts (externally visible as compared to
entognathous mouth parts of the Diplura, Protura and Collembola which are
sunk into the head and thus not imediately visible). They have long filiform
antennae with as many as, or more than 30 segments. The abdomen has eleven
segments generally ending in three 'tails' consisting of two cerci and a
telson. They are commonly represented by the Silverfish and the firebrats
often found in houses and bakeries respectively.
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