diatonic

The keyboard had eleven, twelve, even thirteen keys in diatonic succession without semitones.

In the Diatonic genus, for example, a semitone must be followed by two tones, so as to make up the interval of a Fourth.

On the Diatonic scale, according to the same writer, the species of an Octave is distinguished by the places of the two semitones.

The scholars who connect the ancient Modes with the species generally confine themselves to octaves of the Diatonic genus.

One was Diatonic, of the 'colour' or variety which Ptolemy recognises as the prevailing one, viz.