Hermaeus wrote On Egyptians, book 1. Plutarch, On Isis and Osiris 37, cites him: Osiris translated means “mighty”. In chapter 42 Plutarch adds Hermaeus’s other name of the god, Omphis, which he says means “benefactor.” The same Plutarch context distinguishes Egyptian Arsaphes from Osiris and mentions Dionysus as son of Zeus and Isis.
The fragments are collected in Müller's Fragments of the Greek Historians (vol. 4, p. 427). He is dated, uncertainly, to the first century CE. This is a cult-historian of Egypt, not Hermaeus the Indo-Greek king of the Paropamisadae.
The Greek is Osiris-etymology, not a Bactrian royal life.
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On Egyptian Deities
Ἀπόσπασμα
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