Second Species

SECOND species counterpoint involves placing two minims (half notes) against each note of the cantus firmus. The rules which the notes must satisfy are:

• The first minim must always be consonant with the CF.
• The second minim may be dissonant if it is approached and left by step (figure 1). If it moves by skip it must be consonant.
• Fifths on the first minim of successive bars are not allowed (figure 2) unless the intervening note leaps a fourth, fifth, or minor sixth in the same direction as the CF (figure 2a). The same constraint applies to octaves on the first minim of successive bars.
• The first note in the penultimate bar must be a perfect fifth above the CF, followed by a major sixth above the CF (figure 3).
As in first species, the counterpoint must begin a 5th or 8ve above the CF, and end an 8ve above the CF.

figure 1	figure 2	figure 2a	figure 3
correct use of dissonance	bad 5ths	5ths mitigated by leap (a 4th).	closing formula

An example from Gradus

• Since this is in the Aeolian mode, the closing formula has required both minims in the penultimate bar to be sharpened.
• A minim rest has been used in the first bar. (Fux recommends this alternative, but the applet does not currently allow it.)
• Only one unison has been used (on the weak beat of the 6th bar).
• Melodic direction reverses after an ascending leap (an 8ve) in bar 4
• The consecutive 8ves on the downbeat in bars 8 & 9 have been mitigated by the intervening leap of a fourth.

On using the applet