Vasiform orifice: in Aleurodidae, an ovate, triangular or semicircular opening on the dorsum of the last abdominal segment. Veinlets: in Orthoptera, are the minute transverse ribs or ridges between the longitudinal veins. Veins: the chitinous, rod-like structures supporting the wings, and especially those extending longitudinally from base to the outer margin nerves nervures; nervules. Velum: a membranous appendage of the spurs at the apex of anterior tibia in bees a broad process at inner end of fore tibia. Velum penis: the thin membranous covering of the male intromittent organ also applied to ether covering or shield-like structures of the penis. Velutinous: velvety: clothed with dense, soft, short hair, like velvet. Vena: a vein. Vena dividens: that longitudinal vein of secondaries that marks the beginning of the anal area: = anal 1 (Comst.). Vena plicata: on the wings of Dermaptera, the vein around which the folding occurs. Vena spuria: = spurious vein: q.v. Venation: the system of chitinous frame-work supporting the wings: in Lepidoptera, the veins are usually referred to by numbers which are as follows: on primaries: 1 = anal; 2 = cubitus 2; 3 = cubitus 1: 4 = media 3; 5 = media 2; 6 = media 1; 7 = radius 5; 8 = radius 4; 9 = radius 3; 10 = radius 2; 11 = radius 1; 12 = subcosta: on secondaries: 1, 1a, 1b = anal; 2 = Cubitus; 3 = cubitus 1; 4 = media 3: 5 = media 2; 6 = media 1; 7 = radius 1; 8 = sub-costa. See plate III for typical venations of all orders. Venter: the belly: under surface of abdomen as a whole and of each ring. Ventose: inflated; puffed out. Ventrad: extending or directed toward the under side. Ventral: pertaining to the under surface of abdomen: in Diptera, that face of the leg which is inferior when laterally extended. Ventral chain: refers to the series of ganglia of the nervous system. Ventral comb: in Trichoptera, a transverse row of fine teeth on venter. Ventral diaphragm: is a fine membrane covering the central nerve cords and ganglia: also called ventral heart. Ventral heart: = ventral diaphragm, q.v. Ventral plate: a thickening of the blastoderm of an egg from which the embryo, but not the amnion or serosa is formed. Ventral scale: in Diaspinae, the under part of the puparium, interposed between the insect and the plant. Ventral tube: in Collembola, a tube or tubercle proceeding from the ventral side of the first abdominal segment. Ventricose: with a big belly: distended; inflated. Ventriculus: the true stomach, = chylific ventricle; q.v. Ventri-meson: the middle line of the ventral surface of the body. Ventro-cephalad: toward the lower side and anteriorly. Ventro-dorsad: extending from belly to back. Venules: the branches of the main veins. Vermian: worm-like. Vermicular: worm-like, tortuous: resembling the tracks of a worm. Vermiculate: worm-like in form: a marking with wormlike tracings. Vermiform: worm-shaped. Vernal: appearing in spring.