Uzel, with the majority of students, regards the paired organs as mandibles and the unpaired as an epipharynx.
Organs of similar type on the maxillae and epipharynx appear to exercise the function of taste.
The Nepidae breathe by means of a pair of long, grooved tail processes (really out-growths c, labrum; d, epipharynx.
Behind the labrum arises a process - the epipharynx - which in some blood-sucking insects becomes a formidable piercing-organ.
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