ect fourth, as in Fig. 56_a_, is good.

The minor seventh, and the major and minor ninth of a chord, may be used
freely on any but the first quarter, but must be consonant with the other
part. [Fig. 57.]

[Illustration: Fig. 57.]

The first and third species may be mixed, as in Fig. 58.

[Illustration: Fig. 58.]

The second species may be used in one part and the third in the other, also
six notes in one part and two in the other, and six in one and three in the
other. All tones appearing simultaneously, must comply with the suggestions
for tones appearing on the weak beat given in previous lessons, where both
parts have other than the first species. [Fig. 59.]

[Illustration: Fig. 59.]

The cadences in Fig. 60 are good, and will suggest others.

[Illustration: Fig. 60.]

EXERCISES

To cantus firmus _a_ write one counterpoint above and one below, in the
third species.

To cantus firmus _b_ write counterpoints in six notes, one above and one
below. [Fig. 52.]

Write one eight-measure phrase, mixing the first and third species. [Fig.
58.]

Write two eight-measure phrases, using third species in both parts. [Fig.
55.]

CANTI FIRMI

[Illustration: Fig. 61.]

LESSON VI

FOURTH SPECIES

[Illustration: Fig. 62.]

This species is the same as the second, except that the last note of the
measure is tied to the first note of the next, forming a syncopation. As in
the second species, the first note of the counterpoint should form a
unison, octave or fifth, and when the counterpoint begins on the second
half it may also be an imperfect consonance.

When the counterpoint begins on the first half, the second half is treated
the same as the second half of succeeding measures, described in the next
paragraph.

After the first measure, the second half of the measure should contain a
consonance (Fig. 63_a_), the first half a consonance (_b_), or dissonance
(_c_), preferably the latter, in which case a suspension is formed. This is
the most desirable form of syncopation. When the first half contains a
dissonance, the counterpoint must descend--or ascend in retardation
(_d_)--one degree to an imperfect consonance (_c_). When the first half is
a consonance, it may be left by a skip to some other chord-tone (_e_), or
by degreewise progression (_f_). In the latter case the second note is
non-harmonic, and therefore should not be used to prepare a syncopation
except as in Fig. 63_d_ (Retardation of the