Now these distinctions were in no way due to the statute of the Twelve Tables, which, with the simplicity proper to all legislation, conferred reciprocal rights of succession on all agnates alike, whether males or females, and excluded no degree by reason merely of its remoteness, after the analogy of family heirs; but it was introduced by the jurists who came between the Twelve Tables and the imperial legislation, and who with their legal subtleties and refinements excluded females other than sisters altogether from agnatic succession.
"The Institutes of Justinian"
Caesar Flavius Justinian
7 In agnatic succession the established rule was that the right of accepting the inheritance could not pass from a nearer to a more remote degree; in other words, that if the nearest agnate, who, as we have described, is called to the inheritance, either refuses it or dies before acceptance, the agnates of the next grade have no claim to admittance under the Twelve Tables.
"The Institutes of Justinian"
Caesar Flavius Justinian
But we, in our desire to have the law as complete as possible, have enacted in the constitution which in our clemency we have issued respecting the rights of patrons, that in agnatic succession the transference of the rights to accept from a nearer to a remoter degree shall not be refused: for it was most absurd that agnates should be denied a privilege which the praetor had conferred on cognates, especially as the burden of guardianship fell on the second degree of agnates if there was a failure of the first, the principle which we have now sanctioned being admitted so far as it imposed burdens, but rejected so far as it conferred a boon.
"The Institutes of Justinian"
Caesar Flavius Justinian