Extracts from chapters lxv-lxxi:
But at the height of his happiness and his confidence in his family and its training, Fortune proved fickle. He found the two Julias, his daughter and granddaughter, guilty of every form of vice, and banished them … He informed the Senate of his daughter's fall through a letter read in his absence by a quaestor, and for very shame would meet no one for a long time, and even thought of putting her to death.… After Julia was banished, he denied her the use of wine and every form of luxury, and would not allow any man, bond or free, to come near her without his permission, and then not without being informed of his stature, complexion, and even of any marks or scars upon his body. It was not until five years later that he moved her from the island to the mainland and treated her with somewhat less rigour.… He would not allow the child born to his granddaughter Julia after her sentence to be recognized or reared.
… In early youth he incurred the reproach of sundry shameless acts. Sextus Pompeius taunted him with effeminacy; Marcus Antonius with having earned adoption by his uncle through unnatural relations; and Lucius, brother of Marcus Antonius, that after sacrificing his honour to Caesar he had given himself to Aulus Hirtius in Spain for three hundred thousand sesterces, and that he used to singe his legs with red-hot nutshells, to make the hair grow softer.
… That he was given to adultery not even his friends deny, although it is true that they excuse it as committed not from passion but from policy, the more readily to get track of his adversaries' designs through the women of their households. Marcus Antonius charged him, besides his hasty marriage with Livia, with taking the wife of an ex-consul from her husband's dining room before his very eyes into a bed-chamber, and bringing her back to the table with her hair in disorder and her ears glowing; … that his friends acted as his panders, and stripped and inspected matrons and well-grown girls, as if Toranius the slave-dealer were putting them up for sale.
Of these charges or slanders (whichever we may call them) he easily refuted that for unnatural vice by the purity of his life at the time and afterwards ... He could not dispose of the charge of lustfulness and they say that even in his later years he was fond of deflowering maidens, who were brought together for him from all quarters, even by his own wife.
[Suetonius, De Vita Caesarum, 2 Vols., trans. J. C. Rolfe (Cambridge, Mass.: Harvard University Press, 1920), pp. 123-287. (This text is part of the Internet Ancient History Sourcebook.)]