The Fitzwilliam Museum, Cambridge (U.K.) has several paintings of Balthasar van der Ast. One of them is this oil-painting on panel entitled “A vase of flowers with shells on a ledge”.  It is dated 1640–1649, thus from his Delft period .
On this painting we see two land shells, both to the right of the vase of flowers, and both in a dorsal view. The one closest to the vase is somewhat hidden in the shadows, but both are undoubtedly the same species: Liguus virgineus (L., 1758); this species does occur on the West Indian island of Hispaniola.