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. Internal veins: in Lepidoptera, from one to three in number, run free from base to outer margin near hind angle; never branched;1a to is in the numerical series: = anal veins (Comst.). Interneural: between the nerves (or veins) of wings. Interno-mandibular: applied to one of the pairs of salivary glands in bees, situated at the inner side of base of mandible. Internomedian: in Orthoptera; = cubitus (Comst.); q.v. Interocular: between the eyes. Interplical: lying between folds; specifically applied to the alternate ridges and grooves in anal area of secondaries of Orthoptera. Interposed sectors: in Odonata; the shorter longitudinal veins occurring in the wings of some species between the chief veins; = supplementary sectors. Interrupted: broken in continuity, but with the tips of the broken parts in a right line with each other. Intersegmental: = interarticular; q.v. Interspace: Coleopteran; the plane surface between elytral striae: Lepidoptera spaces between wing veins not included in closed cells. Interspaceal: occurring in the interspaces between two wing veins or two elytral striae. Interstice -tium: space between two lines, whether striate or punctate. Interstitial line: the elevated ridge between two striae or series of punctures. Interval: the space or time between two structures, sculptures or periods of development. Interventricular: the inner valve between the chambers of the heart. Interventricular valvule: of heart, lies in front of seluilunar valve. Intervenular: in thespace between two veins. Intestinal caecum: that point of the large intestine in front of the junction with the small intestine. Intestine: that part of the alimentary canal through which the food passes from the stomach, in which absorption is completed and the excretions are formed for expulsion. Intima: the lining membrane of the trachea: see endotrachea. Intorted: turned or twisted inwardly. Intra-: within: between. Intra-alar bristles: in Diptera; a row of two or three between the supra-alar and dorso-central groups. Intracellular: occurring within the cell or in a cell. Infra-humeral bristles: in Diptera calyptrata; occur immediately in front of the thoracic suture, between the humeral callus and the presutural depression. Infra-ocular: situated within the eye, actually or apparently. Intra-pulmonary: that method of respiration which does not involve movements of the outer body wall and is confined to the respiratory organs. Intrauterine: applied to development, when the young hatch within the vagina of the mother.