Echinodermates (Gorgonocephalus) have radially symmetrical body as secondary character. The radial symmetry is due to sedentary or sessile model of life. The larva is bilaterally symmetrical. The molluscs (Pila) have asymmetrical body The development includes larva. Polygordius (Annelida) is a bilaterally symmetrical animal. Larva is also formed. Gorgonia (Coelenterata) has radially symmetrical body with tissue grade of body organisation.