We present evidence supporting the proposition that amphiphiles displaying lyotropic mesomorphism (and are : thus swelling in water) predominantly have double layers of polar headgroups running through lamellae of its pure, crystalline form. In contrast, we propose that amphiphiles NOT displaying lyotropic mesomorphism (and are thus nonswelling in water) predominantly have monolayers of polar headgroups running through the lamellae of its pure, crystalline form. Water can simply penetrate the double-layered headgroup sheets in the "swelling" amphiphiles, an impossibility in the "nonswelling" class. The latter chemicals are thus expected to be efficient scavengers of hydrophobic fluids in the presence of water.