Alongside her depiction of the Carolina Sphinx Moth (Manduca sexta), Merian showed the hairy caterpillar of a Flannel Moth (Megalopygidae). This caterpillar is poisonous to touch, as Merian found out to her cost:  ‘if one touches them with the hand, it swells up immediately and is very painful’. Visiting Suriname in 1805, Baron Albert von Sack sought out one of these caterpillars to test her theory.