Description: Phalium granulatum (Born, 1778) - apertural view of a Scotch bonnet snail shell, 2.25 cm tall. Family Cassidae - cassid snails prey on echinoids (and other echinoderms) in shallow-water marine sandy substrates and reef facies in tropical to temperate settings. Date: 16 March 2011, 20:14. Source: Phalium granulatum (Scotch bonnet snail) (San Salvador Island, Bahamas) 2. Author: James St. John.