A Dictionary of Greek and Roman biography and mythology

2. Of Alexandria, a Stoic philosopher and grammarian, and an historical writer, was the chief librarian of the Alexandrian library, or at least of that part of it which was kept in the temple of Serapis. He is called ἱερογραμματεύς, that is, keeper and expounder of the sacred books. (Tzetz. in Hom. Il. p. 123. 11, 28, p. 146. 16; Euseb. Praep. Evang. 5.10.) He was the teacher of Dionysius of Alexandria, who succeeded him, and and who flourished from the time of Nero to that of Trajan. (Suid. s. v. Διονύσιος Ἀλεξανδρεύς.) This fixes his date to the first half of the first century after Christ; and this is confirmed by the mention of him in connexion with Cornutus. (Suid. s. v. Ὠριγένης; Euseb. Hist. Eccl. 6.1.9.) He accompanied Aelius Gallus in his expedition up Egypt [GALLUS, AELIUS], and made great professions of his astronomical knowledge, but incurred much ridicule on account of his ignorance (Strab. xvii. p.806): but the suspicion of Fabricius, that this account refers to a different person, is perhaps not altogether groundless. (Bibl. Graec. iii. p. 546.) He was afterwards called to Rome, and became the preceptor of Nero, in conjunction with Alexander of Aegae. (Suid. s. v. Ἀλέξανδρος Αἰγαῖος.)

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