ἐπιστόλιον
From LSJ
ἀλλὰ τί ἦ μοι ταῦτα περὶ δρῦν ἢ περὶ πέτρην → why all this about trees and rocks, why all these things we have nothing to do with
English (LSJ)
τό, Dim. of ἐπιστολή, Epicur.Fr.143, UPZ69.3,5 (ii B.C.), Plb.31.16.3, Plu.Ages.13, M.Ant.1.7, POxy.1481.3 (ii A.D.), etc.