n
each part in turn.

CANTI FIRMI

[Illustration: Fig. 100.]

LESSON XIII

SECOND SPECIES IN TWO PARTS

[Illustration: Fig. 101.]

The suggestions for second species in both parts, in two-part counterpoint,
apply for the two parts having the second species in three-part
counterpoint.

Accidental harmonies sometimes appear on the weak beat. All tones in this
accidental harmony foreign to the chord on the strong beat must be treated
as dissonances. This must be regarded whenever two or more parts have other
than the first species. [Fig. 102.]

[Illustration: Fig. 102.]

At Fig. 102_a_, the accidental harmony _f-a-c_ is on the weak beat. The _f_
and _a_, being foreign to the chord _c-e-g_ on the strong beat, are
correctly treated as dissonances. At _b_, the _f_ and _a_ are left by skip,
which is not permitted.

The second species may be written continuously in all parts; the tones
appearing on the weak beat must be harmonically related to one another, and
those foreign to the chord on the strong beat must be treated as
dissonances. [Fig. 103.]

[Illustration: Fig. 103.]

The first and second species may be mixed, as in Fig. 104.

[Illustration: Fig. 104.]

The cadences in Fig. 105 are good, and will suggest others. Those with
first species in all parts may also be used.

[Illustration: Fig. 105.]

EXERCISES

To cantus firmus _a_ write a counterpoint in the second species in one
part. Write three settings, as directed in the previous lesson.

Write two eight-measure phrases mixing the first and second species in all
parts.

To cantus firmus _b_ write counterpoints in the second species in the other
two parts. Write two settings, with the cantus firmus in different parts.

CANTI FIRMI

[Illustration: Fig. 106.]

LESSON XIV

THIRD SPECIES

[Illustration: Fig. 107.]

The suggestions for third species in two-part counterpoint, as well as
those for writing the second species in three-part counterpoint, apply when
writing third species in three-part counterpoint.

The cadences at Fig. 108 are good, and will suggest others.

[Illustration: Fig. 108.]

EXERCISES

To cantus firmus _a_ write third species in one part. Write three settings
as previously directed.

To cantus firmus _b_ write second species in two parts, as previously
directed.

Write one eight-measure phrase, using second species in all parts.

CANTI FIRMI

[Illustration: Fig. 109.]

LES