The anterior maxillæ lie behind the mandibles, and like them are unconnected with each other. They retain much more of the primitive structure of a gnathite than the mandibles, in which parts quite distinct in the maxillæ are condensed or suppressed. The constituent pieces are seen in fig. 20. There is a two-jointed basal piece, consisting of the _cardo_ (_ca_) and the _stipes_ (_st_). The cardo is a transverse plate bent upon itself, and enclosing muscles; it is attached to the outward-directed pedicel of the occipital frame, and carries the vertical stipes. To the side and lower end of the stipes is attached the five-jointed palp (_pa_), a five-jointed limb used in feeding and in exploration, while the lacinia (_la_) and galea (_ga_) are articulated to its extremity. The lacinia is internal and posterior to the galea; it is broad above, but narrows below to a bifid tooth of dense chitin; its inner surface is beset with a cluster of strong setæ. The galea is more flexible, and forms an irregular three-cornered prism with an obliquely truncated end, upon which are many fine hairs. A flexible and nearly transparent flap connects the inner edges of the stipes and cardo, and joins both to the labium. The muscles which move the bases of the maxillæ spring from the crura, central plate, and keel of the tentorium. On the posterior surface of the head, below the occipital foramen, we find a long vertical flap, the labium, which extends downwards to the opening of the mouth. It represents a second pair of maxillæ, fused together in their basal half, but retaining elsewhere sufficient resemblance to the less modified anterior pair to permit of the identification of their component parts. The upper edge is applied to the occipital frame, but is neither continuous with that structure nor articulated thereto. By stripping off the labium upwards it may be seen that it is really continuous with the chitinous integument of the neck. The broad shield-like base is incompletely divided by a transverse hinge into an upper and larger piece, the _submentum_, and a distal piece, the _mentum_. To the mentum are appended representatives of the galeæ (here named _paraglossæ_) and laciniæ, while a three-jointed palp with an additional basal joint (distinguished as the _palpiger_) completes the resemblance to the maxillæ of the first pair.[51] In front of the labium, and lying in the cavity of the mouth is a chitinous fold of the oral integument, the _lingua_, which lies like a tongue in the floor of the mouth. The common duct of the salivary glands enters the lingua, and opens on its hinder surface. The lingua is supported by the chitinous skeleton represented in the figures of the salivary glands. (Chap. vii., _infra_.) [51] The homology of the labium with the first pair of maxillæ is in no other Insects so distinct as in the Orthoptera. The epipharynx, which is a prominent part in Coleoptera and Diptera, is not recognisable in Orthoptera.