Characteristics of Porifera:
(i) Cellular level of organisation.
(ii) Digestion is intracellular.
(iii) Appendages are absent in poriferans.
Characteristics of Cnidaria:
(i) Tissue level of organisation.
(ii) Digestion is both extracellular and intracellular.
(iii) They have appendages in the form of tentacles.