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“The efferent duct of the thoracic salivary glands (ductus salivalis) perforates the hypopharynx, more or less near the base, that the saliva may be ejected through the canal into the wound, or that it may be conducted along the labella. Very rarely the salivary duct, perforating the hypopharynx, is continued in the shape of a free, very slender tube.

“The salivary duct behind the base of the hypopharynx forms the receptacle or receptaculum, provided with retractor and levator muscles.”

Fig. 83.—Labrum-epipharynx (lbr and eph) and hypopharynx (hyp) of Tabanus brominus: oe, posterior cylindrical portion of the œsophagus; a, anterior swollen portion of the same; ph, pharynx; ph.m, pharyngeal muscle; p.ph, protractor muscle of the pharynx; r.oe, retractor muscle of the œsophagus; r.ph, retractor muscle of the pharynx; f.oe, flexor muscle of the pharynx; t.oe, twisting muscle of the œsophagus; s.r, receptacle of the salivary duct; l, its elevator muscle; s, its retractor muscle; cl, clypeus.—After Meinert.