The following points highlight the fifteen interesting forms of Mollusca. The forms are: 1. Solen 2. Pecten 3. Mytilus 4. Teredo 5. Aplysia 6. Doris 7. Aeolis 8. Onchidium 9. Patella 10. Spiratella 11. Cypraea 12. Loligo 13. Octopus 14. Argonauta 15. Nautilus. Molluscs: Form # 1. Solen: Solen is a burrowing bivalve and is generally called 'Razor shell'. The [...]
The nervous system in Molluscs (Figs. 16.68-16.70) presents numerous diversities. It exhibits gradual coming up of complexities from simple to complex which can be marshalled into one perspective—the nervous co-ordination. Prior to the description of the nervous system in different forms of Molluscs a basic plan of the Molluscan nervous system is to be considered first. Hypothetical Plan of Molluscan [...]
1. Skin and mantle. 2. Molluscan gills or ctenidia or branchiae and 3. Lungs or pulmonary sac. The outer covering of the body (skin) and mantle usually act as accessory respiratory organs. 1. Skin and Mantle — as Respiratory Organs: Skin appears to be the simplest type of respiratory structure encountered in Molluscs. It acts as a respiratory organ in [...]