In most cases the entrance of the chorus took place at the conclusion of the ‘prologue’ or introductory scene upon the stage; and the march in was accompanied by a chant, which was called the ‘parodos’, or entrance-song.[909] However, in a considerable number of plays there was no parodos at all, but the chorus entered the orchestra in silence, while the first act of the drama was in progress, and then commenced a musical dialogue with the actors upon the stage. Instances of this mode of entrance are to be found in such tragedies as the Electra of Sophocles and the Orestes of Euripides.[910] A few plays do not conform to either of these two conventional types. Occasionally, for instance, there is no prologue, and the play begins with the parodos, as in the Supplices and Persae of Aeschylus. This was no doubt the old-fashioned mode of commencement, derived from the times when the drama was still entirely lyrical. Then again, in the Eumenides the parodos is sung on the second entrance of the Furies, after their arrival at Athens. In the Supplices of Euripides the chorus are seen kneeling upon the stage in supplication when the play commences. There they remain in silence during the performance of the prologue, and then proceed to sing an ode, in place of the usual parodos, from their position on the stage. In the Clouds it appears that the chorus chant the first two odes behind the scenes, and then enter the orchestra silently. The Rhesus commences with a dialogue in anapaests between Hector and the chorus. The next point to be considered is the position taken up by the chorus after entering the orchestra. On most occasions, as already stated, the chorus came in by the western side, drawn up in rectangular formation, with the stage on its right hand and the spectators on its left. It advanced half-way into the orchestra, then came to a halt, and each member of the chorus turned round to the right, so as to face the stage. By this manœuvre the whole chorus was made to look towards the stage, and the arrangement by files was converted into one by ranks. For instance, the tragic chorus, which had entered three abreast and five deep, now stood before the stage five abreast and three deep. The coryphaeus and principal choreutae stood in the back line, and retained their position nearest to the spectators, and furthest away from the stage. This position they kept throughout the performance.[911] In a similar manner the comic chorus, after entering the orchestra four abreast and six deep, would halt in front of the stage, go through the manœuvre just described, and convert itself into a body standing six abreast and four deep. There is no information as to the position of the coryphaeus in the comic chorus. But there can be no doubt that, like the tragic coryphaeus, he stood in the back row, as near as possible to the spectators.