This watercolour, which is signed by Merian, shows the caterpillar of the Dark Dagger Moth, a common European species. Merian has carefully shown the long dark hairs which are one of the caterpillar’s distinguishing features, as well as its black, red and white markings. She illustrated the same caterpillar in the third volume of her publication Der Raupen wunderbare Verwandlung (The Wonderful Transformation of Caterpillars).