Es kommen einige solcher Verse in Vergils Aeneis vor, z. B. allein im vierten Buch 44, 361, 400, 503 und 516. Donat nennt solche Verse in seiner Vergil-Vita „versus imperfectos“ (§ 41, ed. C. Hardie, Oxonii 1960, p. 11) und Servius schreibt in seiner Vergil-Vita (l.c. p. 18 ):
Augustus vero, ne tantum opus periret, Tuccam et Varium hac lege iussit emendare, ut superflua demerent, nihil adderent tamen: unde et semiplenos eius invenimus versiculos, ut [Aen. i. 534] ‚hic cursus fuit’
Zur Erklärung vgl. u. a. P. Vergili Maronis Aeneidos liber quartus, edited by Arthur Stanley Pease, Darmstadt 1967, S. 123f.:
In explanation of the half-lines there are two conflicting theories. By some it is supposed that they were left by the poet intentionally unfinished, for greater emphasis, for certain pathetic effects, or to relieve the monotony of the hexameter verse. [...] The other and more probable explanation ... makes the half-lines not intentional but the result of the incompleteness of the Aeneid....
Bei Stiernhielm vermutlich "intentional".
Iubeo te optime valere.