In this line by line commentary l have attempted to discuss all matters textual and linguistic on which a reader might resort to a commentary for aid. There is, naturally, a pronounced emphasis on textual criticism; literary comment is interwoven with my arguments as the play unfolds. I have endeavoured to cite Greek with sufficient generosity to enable the reader to form a different judgement from my own from the material I have furnished. Considerable space has also been devoted to matters mythological and religious, as the nature of the play demands. I conclude with an Endnote on the marginal annotations found in L. Three appendices follow: on the question of scenery, on alliteration in ancient poetry and poetic theory. and on a textual problem in the prologue to Euripides' Phrixus. As no new evidence has emerged either to enhance our knowledge of the paradosis or to indicate the date and general background of the play, I would prefer at this stage to direct the reader to A.S.Owen's introduction to his Clarendon edition of 1939 rather than burden this work further with a formal introduction. I conclude with a general bibliography of works often cited.