This engraving belongs to a series of four designs for plates, each depicting a mythological marine figure in the center (Arion, Thetis, Neptune and Galathea) and sea monsters, nymphs, tritons, and other bizarre creatures in the border. The plates, probably intended for display only, were to be rendered in precious metals. The sea goddess Thetis is represented holding a conch and sitting on the edge of a gigantic Pecten Jacobaeus (a scallop shell). Smaller, more realistic shells are scattered at her feet and around the rim, highlighting the fecundity of her realm and enriching the plate’s decorative effects.