  The only book of Philodemus cited in extant ancient literature is his Collection of the Philosophers, the tenth book of which is Diogenes Laertius’ source (10.3) for the statement that Epicurus’ three brothers, Neocles, Chairedemos, and Aristoboulos, did philosophy together with him (sunephilosophoun). The Herculaneum library has given us fragmentary remains of a number of works on the history of various schools, particularly one (called by earlier editors the Index Academicorum) on the Platonic Academy, from Plato to Aristos of Ascalon, and another on the Stoa, from Zeno to Panaetius (the Index Stoicorum), and it is possible that they, along with other, more fragmentary books, belonged to the Collection. These books contain numerous historical and biographical anecdotes along with chronological indications, many from Apollodorus’ Chronicle, and fit well alongside the genre of philosophical histories sometimes referred to as ‘Successions’ (diadochai) of philosophers (see Arrighetti 2003). Philodemus even refers to his own relations with some of the later Academics, especially Antiochus of Ascalon (see Dorandi 1990b).