INSTITUTION OF HEIR, civil law. The act by which a testator nominates one or more persons to succeed him in all his rights, active and passive. Poth. Tr. des Donations Testamentaires, c. 2, s. 1, 1; Civ. Code of Lo. art. 1598; Dig. lib. 28, tit. 5, l. 1; and lib. 28, tit. 6, l. 2, 4.