What ’vaileth truth?
This is the proper form of the rondeau. Other forms deviating from it are modelled on the schemes:
a a b b a b b a + r b b a a b + r(Wyatt, p. 24),
a a b b a + r c c b + r a a b b a + r (ib. p. 26),
a b b a a b + r a b b a + r (D. G. Rossetti, i. 179).
Austin Dobson, Robert Bridges, and Theo. Marzials strictly follow the form quoted above.
Another form of the rondeau entirely deviating from the above is found in Swinburne, A Century of Roundels,[208] where he combines verses of the most varied length and rhythm on the scheme A B A + b B A B A B A + b where b denotes part of a verse, rhyming with the second, but repeated from the beginning of the first verse and consisting of one or several words (cf. Metrik, ii, §§ 584, 585)
§ 325. The triolet and the villanelle are unusual forms occurring only in modern poets, e.g. Dobson and Gosse.
The triolet, found as early as in Adenet-le-Roi at the beginning of the thirteenth century, is a short poem of eight mostly octosyllabic verses, rhyming according to the formula a b a a a b a b, the first verse recurring as a refrain in the fourth, the first and second together in the seventh and eighth place. Two specimens have been quoted, Metrik, ii, § 586
§ 326. The villanelle (a peasant song, rustic ditty, from villanus) was cultivated by Jean Passerat (1534–1602); in modern poetry by Th. de Banville, L. Baulmier, &c. It mostly consists of octosyllabic verses divided into five stanzas (sometimes a larger or smaller number) of three lines plus a final stanza of four lines, the whole corresponding to the scheme a1 b a2 + a b a1 + a b a2 + a b a1 + a b a2 + a b a1 a2. Hence the first and the third verses of the first stanza are used alternately as a refrain to form the last verse of the following stanzas, while in the last stanza both verses are used in this way. A villanelle by Gosse on this model consisting of eight stanzas, perhaps the only specimen in English literature, has been quoted, Metrik, ii, § 587