DETERMINABLE FEE. Also called a qualified or base fee, is one which has a quality subjoined to it, and which must be determined whenever the qualification annexed to it is at in end. A limitation to a man and his heirs on the part of his father, affords an example of this species of estate. Litt. §254; Co. Litt. 27 a, 220; 1 Prest. on Estates, 449; 2 Bl. Com. 109; Cruise, tit 1, §82; 2 Bouv. Inst; n., 1695.