We have now reviewed all the passages in Aristoxenus which can be thought to bear upon the question whether the [Greek: harmoniai] or Modes of early Greek music are the same as the [Greek: tonoi] or Keys discussed by Aristoxenus himself. The result seems to be that we have found nothing to set against the positive arguments for the identification already urged. It may be thought, perhaps, that the variety of senses ascribed to the word [Greek: harmonia] goes beyond what is probable. In itself however the word meant simply 'musical scale[1].' The Pythagorean use of it in the sense of 'octave scale,' and the very similar use in reference to diagrams which represented the division of that scale, were antiquated in the time of Aristoxenus. The sense of 'key' was doubtless limited in the first instance to the use in conjunction with the names Dorian, &c., which suggested a distinction of pitch. From the meaning 'Dorian scale' to 'Dorian key' is an easy step. Finally, in reference to genus [Greek: harmonia] meant the Enharmonic scale. It is not surprising that a word with so many meanings did not keep its place in technical language, but was replaced by unambiguous words, viz. [Greek: tonos] in one sense, [Greek: systêma] in another, [Greek: genos enarmonion] in a third. Naturally, too, the more precise terms would be first employed by technical writers. [Footnote 1: So in Plato, _Leg._ p. 665 a: [Greek: tê dê tês kinêseôs taxei rhythmos onoma eiê, tê d' au tês phônês, tou te oxeos hama kai bareos synkerannymenôn, harmonia onoma prosagoreuoito.]] § 23. _The Seven Species._ (See the Appendix, Table I.) In the _Harmonics_ of Aristoxenus an account of the seven species of the Octave followed the elaborate theory of Systems already referred to (p. 48), and doubtless exhibited the application of that general theory to the particular cases of the Fourth, Fifth, and Octave. Unfortunately the existing manuscripts have only preserved the first few lines of this chapter of the Aristoxenean work (p. 74, ll. 10-24 Meib.). The next source from which we learn anything of this part of the subject is the pseudo-Euclidean _Introductio Harmonica_. The writer enumerates the species of the Fourth, the Fifth, and the Octave, first in the Enharmonic and then in the Diatonic genus. He shows that if we take Fourths on a Diatonic scale, beginning with Hypatê Hypatôn (our _b_), we get successively _b c d e_ (a scale with the intervals 1/2 1 1), _c d e f_ (1 1 1/2) and _d e f g_ (1 1/2 1). Similarly on the Enharmonic scale we get-- Hypatê Hypatôn to Hypatê Mesôn _b b* c e_ (1/4 1/4 2 ) Parhypatê " " Parhypatê " _b* c e e*_ (1/4 2 1/4) Lichanos " " Lichanos " _c e e* f_ (2 1/4 1/4)