Ptolemy reports in his "Harmonics" (2. 14) that two other theorists, Archytas and Didymus, replaced the ditone with the smaller, just major third with the number ratio of 5:4, making the "pyknon" correspondingly larger . This "pyknon" was divided differently by these two theorists, but in both cases the two intervals were not equal to one another. Archytas, who was the first theorist to give ratios for all of the genera, chose 28:27 and 36:35, and Didymus, some four centuries later, gave 32:31 and 31:30 . In the chromatic genus, the largest interval was called a , —translated as "incomposite" (or "noncomposite") "trihemitone" (; ; ; , prefers a descriptive translation, "an individed interval of three semitones"; uses "trisemitone"), the modern term being "minor third"—leaving a "pyknon" of some type of whole tone to be divided into two semitones. There is a larger number of variations in the tuning of the chromatic than in the enharmonic. Up to the beginning of the 4th century BC the chromatic "pyknon" spanned a major whole tone with a 9:8 ratio, and this was divided by Gaudentius into ascending semitone intervals of 256:243 and 2187:2048 . Ptolemy defined two different tunings of the chromatic genus: the "soft" chromatic with a smaller "pyknon" and the "intense" chromatic with a larger one. The unequal semitones dividing the "pykna" were in ratios of 28:27 and 15:14 for the soft chromatic and 22:21 and 12:11 for the intense. The larger remaining interval was 6:5 in the soft chromatic and 7:6 in the intense . A further refinement of tetrachordal construction, according to Aristoxenus, is that the lower interval of the "pyknon" must be smaller than or equal to the upper one . Didymus in the chromatic genus and Archytas in the enharmonic broke this rule, however, and in the "Harmonics" (2. 13) Ptolemy criticized this feature in Didymus, holding that it is unmelodic and out of agreement with the evidence of our ears .