The third may be omitted on the strong beat in this species, provided the
part having fourth species skips to the missing third, as at Fig. 117_a_.

Consecutive fifths, but not octaves, are saved by the suspension. Whenever
they occur, do not use the note of resolution as preparation of a
suspension, or tie it into the next measure (_a_), since it is really the
passing seventh, and that does not lend itself well to either of the above,
except in sequence as at _b_. [Fig. 118.]

[Illustration: Fig. 118.]

The seventh or ninth of a chord, except the major seventh, may be used as
preparation of a suspension when approached by a skip in an upward
direction, as in Fig. 119.

[Illustration: Fig. 119.]

This species may also be written in triple rhythm. [Fig. 120.]

[Illustration: Fig. 120.]

The cadences in Fig. 121 are good, as well as those of the second species.

[Illustration: Fig. 121.]


EXERCISES

To cantus firmus _a_ write fourth species in one part. Write three
settings, as usual.