Vascular | a. [ L. vasculum a small vessel, dim. of vas vessel: cf. F. vasculaire. See Vase, and cf. Vessel. ] [ 1913 Webster ] 1. (Biol.) (a) Consisting of, or containing, vessels as an essential part of a structure; full of vessels; specifically (Bot.), pertaining to, or containing, special ducts, or tubes, for the circulation of sap. (b) Operating by means of, or made up of an arrangement of, vessels; as, the vascular system in animals, including the arteries, veins, capillaries, lacteals, etc. (c) Of or pertaining to the vessels of animal and vegetable bodies; as, the vascular functions. [ 1913 Webster ] 2. (Bot.) Of or pertaining to the higher division of plants, that is, the phaenogamous plants, all of which are vascular, in distinction from the cryptogams, which to a large extent are cellular only. [ 1913 Webster ] Vascular plants (Bot.), plants composed in part of vascular tissue, as all flowering plants and the higher cryptogamous plants, or those of the class Pteridophyta. Cf. Cellular plants, under Cellular. -- Vascular system (Bot.), the body of associated ducts and woody fiber; the fibrovascular part of plants. -- Vascular tissue (Bot.), vegetable tissue composed partly of ducts, or sap tubes. -- Water vascular system (Zool.), a system of vessels in annelids, nemerteans, and many other invertebrates, containing a circulating fluid analogous to blood, but not of the same composition. In annelids the fluid which they contain is usually red, but in some it is green, in others yellow, or whitish. [ 1913 Webster ]
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