TRIPINNATE, a compound leaf three times divided in a pinnate manner. TRIPINNATIFID, a pinnatifid leaf with the segments twice divided in a pinnatifid manner. TRIQUETROUS, having three angles, the faces being concave. TRITERNATE, three times divided in a ternate manner. TRUNCATE, terminating abruptly, as if cut off at the end. TRYMA, drupaceous fruit like the walnut. TUBER, a thickened underground stem, as the potato. TUBERCLE, the swollen root of some terrestrial orchids. TUBERCULATE, covered with knobs or tubercles. TUBEROUS, applied to roots in the form of tubercles. TUBULAR, bell-shaped; applied to a campanulate corolla, which is somewhat tubular in its form. TUMID, swelling. TUNIC, a coat or envelope. TUNICATED, applied to a bulb covered by thin external scales, as the onion. TURBINATE, in the form of a top. TURGID, swollen. TYPICAL, applied to a specimen which has eminently the characteristics of the species, or to a species or genus characteristic of an order. U UMBEL, inflorescence in which numerous stalked flowers arise from one point. UMBELLULE, a small umbel, seen in the compound umbellate flowers of many _Umbelliferæ_. UMBILICATE, fixed to a stalk by a point in the centre. UMBILICUS, the hilum or base of a seed. UNARMED, without prickles or spines. UNCINATE, provided with an uncus, or hooked process. UNCTUOUS, oily. UNDULATE, waved. UNGUICULATE, furnished with a short unguis. UNGUIS, claw, the narrow part of a petal; such a petal is called _Unguiculate_. UNICELLULAR, composed of a single cell, as some Algæ. UNILATERAL, arranged on one side, or turned to one side. UNISEXUAL, of a single sex; applied to plants having separate male and female flowers. URGEOLATE, urn-shaped; applied to a gamopetalous globular corolla with a narrow opening. V VALVATE, opening by valves, like the parts of certain seed-vessels, which separate at the edges of the carpels. VALVATE ÆSTIVATION and VERNATION, when leaves in the flower-bud and leaf-bud are applied to each other by the margins only. VALVES, the portions which separate in some dehiscent capsules. VASCULAR TISSUE, composed of vessels. VEINS, fibro-vascular skeleton of leaves. VELUM, veil; the cellular covering of the gills of an Agaric in its early state. VENATION, the arrangement of the veins. VENTRAL, applied to the part of the carpel which is next the axis. VERNATION, the arrangement of the leaves in the bud. VERRUCOSE, covered with wart-like excrescences. VERSATILE, applied to an anther which is attached by one point of its back to the filament, and hence is very easily turned about. VERTEX, the uppermost point. VERTICAL, perpendicular. VERTICIL, a whorl; parts arranged opposite to each other at the same level, or, in other words, in a circle round an axis. The parts are said to be _Verticillate_.