The present drawing is an initial sketch for De Morgan's 1877 painting Cadmus and Harmonia (The De Morgan Foundation). Taken from Ovid's Metamorphoses (Book IV 563-603), it tells the story of Cadmus, changed into a serpent by Mars, and his wife Harmonia who begs for the same fate. De Morgan depicts Harmonia as a striking young beauty rather than the elderly woman of Ovid's writing. The figure of Harmonia, embraced by her husband in snake form, recalls the central figure in Botticelli's The Birth of Venus (Uffizi Gallery, Florence). The present drawing, with its slight variations from the painting, and its unrealised face, appears to be a very early preparatory sketch for the composition.