Jerome writes to Augustine concerning the nature of the Septuagint of the 4th century (i.e. after Origen’s Hexapla) as follows:
Because, however, in other letters you ask, why my former translation has asterisks and obelisks noted in the canonical books, and afterwards I published another translation without them –I say with your pardon— you do not seem to me to understand, because you have inquired (about them). For this first translation is from the seventy translators and, wherever the marks are, that is the obelisks, it is shown, that the Seventy said more than is contained in the Hebrew; however, where there are asterisks, that is stars which light the way, the reading was added by Origen from the version of Theodotion. And in that (former) translation we translated from the Greek, in this place from the Hebrew itself, we expressed what we were understanding, preserving more importantly the truth of the sense than the order of the words now and then. And I am amazed how you do not read the books of the Seventy in their pure form, as they were published by the Seventy, but rather as emended (emendatos) by Origen or rather corrupted by the obelisks and asterisks, and you do not follow the translation of a Christian man, especially when he (Origen) transferred these additions, which have been added from the edition of a man, a Jew and a blasphemer, after the Passion of Christ. Do you wish to be a true friend of the Septuagint? You should not read these (additions), which are under the asterisks; on the contrary, erase/scrape them from the chapters, so that you might show yourself to be a true patron. If you do this, you will be forced to condemn all the libraries of the churches. For scarcely one or another manuscript/book will be discovered, which has not such additions.
Epistula CXII, 19 Ad Augustinum