A Dictionary of Music and Musicians/Subsidiary
SUBSIDIARY, in a symphonic work, is a theme of inferior importance, not strictly forming part of either first or second subject, but subordinate to one or the other. The spaces between the two subjects, which in the early days before Beethoven were filled up by 'padding' in the shape of formal passages and modulations, are now, in obedience to his admirable practice, occupied by distinct ideas, usually of small scope, but of definite purport. [See vol. i. p. 203b.] The 'Eroica' Symphony affords early and striking examples of subsidiary subjects in various positions. Thus, on the usual dominant passage preceding the 2nd subject appears the plaintive melody:—
which becomes of so much importance in the 2nd part. And the same title belongs also to the fresh subject which appears transiently during the 'working-out' with so much effect:—
Equally noticeable is the phrase in a similar situation in the 4th Symphony,
while the melody which Schubert interpolated as an afterthought in the Scherzo of his great C major Symphony is too well known to require quotation.
These two last however are not worked, and can therefore hardly be classed as 'themes,' but are more of the nature of 'episodes.'
In some cases a Subsidiary acquires so much importance in the working out as to rank as a third subject. The Italian Symphony of Mendelssohn supplies a type of this. The subject—
which appears shortly after the double bar in the 1st movement, though properly speaking merely a Subsidiary, is so insisted upon and elaborated in the working-out and coda as to rival the ist subject itself in importance.
As a notable exception to the rule that a Subsidiary is usually very short, we may mention that in the Rondo Finale of Raff's PF. Quartet in G (op. 202) there occurs a subordinate theme over 60 bars in length.