The work from which these 'Excerpta' are taken was composed, according to Usener, in the year 522. This is proved by the facts that the receiver of the letter is spoken of as Magister Officiorum, a post which he apparently held from Sept. 1, 521, to Sept. 1, 522; and that the Consulship of the two sons of Boethius, which began on Jan. 1, 522, is also referred to. The name of the person to whom the letter is addressed is given as Rufius Petronius Nicomachus. Usener, however, shows good reason for thinking that his final name, the name by which he was known in the consular lists, is omitted, and that his full designation was Rufius Petronius Nicomachus Cethegus, Consul in 504, Magister Officiorum (as above stated) in 521-522, and Patrician. He was probably the same Cethegus whom Procopius mentions[100] as Princeps Senatus, and as withdrawing from Rome to Centumcellae in the year 545 because he was accused of treachery to the Imperial cause[101]. [Footnote 100: De Bello Gotthico iii. 13 (p. 328, ed. Bonn).] [Footnote 101: If Usener be right (and he has worked up this point with great care), we can trace the following links in the pedigree of Cethegus (see pp. 6 and 11): Rufius Petronius _Placidus_, Consul 481. | Rufius Petronius Anicius _Probinus_, Consul 489. | Rufius Petronius Nicomachus _Cethegus_, Consul 504, correspondent of Cassiodorus. Probinus and Cethegus are referred to by Ennodius in his letter to Ambrosius and Beatus, otherwise called his Paraenesis (p. 409, ed. Hartel).] [Sidenote: Its object.] The object of the little treatise referred to evidently was to give an account of those members of the family to which Cassiodorus belonged who had distinguished themselves in literature. The words 'Ex genere Cassiodororum' are perhaps a gloss of the transcribers. At least it does not appear that they would correctly describe the descent of Symmachus and Boethius, though they were relations of Cassiodorus, being descended from or allied to the great house of the Aurelii from which he also sprang. Probably several other names may have been noticed in the original treatise, but the only three as to which the 'Anecdoton' informs us are the three as to whom information is most acceptable--Symmachus, Boethius, and Cassiodorus himself. [Sidenote: Information as to life of Symmachus.]