ἀλλ' οὐκ οἰωνοῖσιν ἐρύσσατο κῆρα μέλαιναν → by no augury could he ward off black death
neuter of a derivative from ἑκών; voluntariness: willingly.
ἑκούσιον: τό свободная воля Plat., Arst.
