This passage does not quite explicitly connect the three kinds of ethos--the diastaltic, the systaltic, the intermediate--with the three regions of the voice; but the connexion was evidently implied, and is laid down in express terms in the pseudo-Euclidean _Introductio_ (p. 21 Meib.). According to this Aristoxenean writer, 'the diastaltic ethos of musical composition is that which expresses grandeur and manly elevation of soul ([Greek: megaloprepeia kai diarma psychês andrôdes]), and heroic actions; and these are employed by tragedy and all poetry that approaches the tragic type. The systaltic ethos is that by which the soul is brought down into a humble and unmanly frame; and such a disposition will be fitting for amatory effusions and dirges and lamentations and the like. And the hesychastic or tranquilly disposed ethos ([Greek: hêsychastikon êthos]) of musical composition is that which is followed by calmness of soul and a liberal and peaceful disposition: and this temper will fit hymns, paeans, laudations, didactic poetry and the like.' It appears then that difference in the 'place' ([Greek: topos]) of the notes employed in a composition--difference, that is to say, of pitch--was the element which chiefly determined its ethos, and (by consequence) which distinguished the music appropriate to the several kinds of lyrical poetry. A slightly different version of this piece of theory is preserved in the anonymous treatise edited by Bellermann (§§ 63, 64), where the 'regions of the voice' are said to be four in number, viz. the three already mentioned, and a fourth which takes its name from the tetrachord Hyperbolaiôn ([Greek: topos hyperboloeidês]). In the same passage the boundaries of the several regions are laid down by reference to the keys. 'The lowest or hypatoid region reaches from the Hypo-dorian Hypatê Mesôn to the Dorian Mesê; the intermediate or mesoid region from the Phrygian Hypatê Mesôn to the Lydian Mesê; the netoid region from the Lydian Mesê to the Nêtê Synemmenôn; the hyperboloid region embracing all above the last point.' The text of this passage is uncertain; but the general character of the [Greek: topoi] or regions of the voice is clearly enough indicated. The three regions are mentioned in the catechism of Bacchius (p. 11 Meib.): [Greek: topous] (MSS. [Greek: tropous]) [Greek: de tês phônês posous legomen einai? treis. tinas? toutous; oxyn, meson, baryn.] The varieties of ethos also appear (p. 14 Meib.): [Greek: hê de metabolê kata êthos? hotan ek tapeinou eis megaloprepes; ê ex hêsychou kai synnou eis parakekinêkos.] 'What is change of ethos? when a change is made from the humble to the magnificent; or from the tranquil and sober to violent emotion.'