Inter-articular: the membranous tissue between joints or segments.
Intercalary -ies: additional or inserted between others; as a vein: plural; added or supplementary longitudinal wing reins: see under specific headings; i.e. anterior, etc.: in Ephemerides, certain longitudinal veins between the 8th (anal) and 9th (1st maxillary) and not branches of either: in Diptera, the anterior intercalary (Loew) = the discoidal, and the posterior intercalary = the cubitus 1 of Comstock: applied to an evanescent sclerite in the embryo between antenna and mandible; also termed premandibular.
Intercostal: between veins or costae; usually in the narrow grooves between veins in the costal region of a wing.
Intercostula: those small, vein-like structures between the normal veins, visible on a wing margin but lost toward the disc.
Intercoxal process: in Coleopteran; a median protrusion of the basal segment of abdomen between the hind coxae.
Intermediate: lying between others in position or possessing characters between two other forms.
Intermediate field: of termini is = discoidal field q.v.
Internal area: in Hymenoptera; the posterior of the three areas between median and lateral longitudinal carina on the metanotum third lateral area.
Internal cell: in Hymenoptera (Pack.) 2d anal (Comst.).
Internal triangle: in Odonata see triangle.