The latest account of the function of this organ is that by Cheshire, who states that the tube made by the maxillæ and labial palpi cannot act as a suction pipe, because it is open above. “This opening is closed by the front extension of the epipharynx, which closes down to the maxillæ, fitting exactly into the space they leave uncovered, and thus the tube is completed from their termination to the œsophagus.” [Illustration: FIG. 26.—Epipharynx of _Phaneroptera angustifolia_: _cl_, clypeus; _lbr. e_, labrum-epipharynx; _t_ _c_, taste cups, both on the clypeal and on the labral regions. ] [Illustration: FIG. 27.—Epipharynx of _Hadenœcus subterraneus_, cave cricket. ] It is singular that this organ is not mentioned in Burmeister’s Manual of entomology, in Lacordaire’s Introduction à l’entomologie, or by Newport in his admirable article _Insecta_ in Todd’s Cyclopedia of anatomy. Neither has Straus-Durckheim referred to or figured it in his great work on the anatomy of _Melolontha vulgaris_. In their excellent work on the cockroach, Miall and Denny state that “The epipharynx, which is a prominent part in Coleoptera and Diptera, is not recognizable in Orthoptera” (p. 45). We have, however, found it to be always present in this order (Figs. 26, 27). We are not aware that any modern writers have described or referred to the epipharynx of the mandibulate orders of insects. Although Dr. G. Joseph speaks of finding taste-organs on the palate of almost every order of insects, especially plant-feeding forms, we are unable to find any specific references, his detailed observations being apparently unpublished. The epipharynx is so intimately associated with the elongated labium of certain Diptera, that, with Dr. Dimmock, we may refer to the double organ as the labrum-epipharynx; and where, as in the lepidopterous _Micropteryx semipurpurella_, described and figured by Walter, and the Panorpidæ (Panorpa and Boreus), the labrum seems pieced out with a thin, pale membranous fold which appears to be an extension of the epipharynx, building up the dorsal end of the labrum, this term is a convenient one to use. In the lower orders of truly mandibulate insects, from the Thysanura to the Coleoptera, excluding those which suck in liquid food, such as the Diptera, Lepidoptera, and Hymenoptera, and the Mecoptera (Panorpidæ) with their elongated head and feeble, small mandibles, the epipharynx forms a simple membranous palatal lining of the clypeus and labrum. In such insects there is no soft projecting or pendant portion, fitted to close the throat or to complete a partially tubular arrangement of the first and second maxillæ.