1. coelom
2. pseudocoelom
3. haemocoel
4. absent
haemocoel
1. Brownish layer
2. Prismatic layer
3. Periostracum
4. Nacre
Nacre
1. Unio
2. Lamellidens
3. Ostrea
4. Pecten
Ostrea
1. Trochophore
2. Tornaria
3. Bipinnaria
4. Muller’s Larva
Trochophore
1. Sepia
2. Dentalium
3. Argonatae
4. Nautilus
Argonatae
1. External shell
2. Internal secretions
3. Ink sac
4. Chromatophores.
Chromatophores.
1. Soft body
2. mantle folds
3. Coelom reduced
4. Ventral ganglionated nerve cord
Ventral ganglionated nerve cord
1. Decapoda
2. Scaphopoda
3. Gastropoda
4. Pelecypoda
Decapoda
1. Aplaceophora e.g. Chaetoderma
2. Polyplacophora e.g. Chiton
3. Cerphalopoda e.g. Dentalium
4. Gastropoda e.g. Achatina
Cerphalopoda e.g. Dentalium
1. Ventral muscular and massive foot
2. Verterbrate like eyes
3. Head degenerated
4. Radula absent
Ventral muscular and massive foot