The head is a small triangular or pear shaped struture its narrow end is directed downwards it is flattened and is placed at right angles to the longitudinal axis of the body it is attached to the thorax by a narrow neck or cervicum. The thick chitinous cuticle covering the head is diveded into a number of plates . The exoskeleton of head which is formed by these plates is known as epicranium and it consists of five sclerites or hard areas there are two epicranial plates joined cover the dorsal and posterior sides of the head .The broad unpaired plate situated between and below the arms of the epicranil sutures is the frons. Below the frons is a broad unpaired rectngular pate the clypeus which forms the lower part of the head .There is a pair of plates covering the sides of the head behind and below the eyes which are called genae or cheeks. The upper lip or labrum is a flap like plate which is movably attached to the lower edge of the clypeus on wach side of the head is a large promient renuform i.e,kidney shaped sessile black area the compound eye .It is divided into a large number of minute hexagonal area or facets.There are four pairs appendages of the heah namely:
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