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short note on Phylum-Mollusca


 ◆The mollusca word comes from latin  word "mollis" means soft.

Mollusca (soft bodied animals)

◆Malacology - study of mollusca.

◆Defination : Molluscs are soft bodied , Bilaterally symmetrical,unsegmented, Coelomate animals; usually shelled head and a dorsal visceral mass.

◆Habitat : Molluscs are mostly marine ,few fresh water and some terrestrial forms.

◆Mollusca is the second largest      phylum of invertebrates.

◆About 1,28,000 species.

◆ body soft covered by mantle usually with an anterior head and a ventral muscular foot.Mentle secrets shell.Shell sometimes vestigial and sometimes in several pieces.

◆Coelom reduced.

◆example : Chiton, Pila(snail), Unio(mussel),Sepia, Loligo(squid), Nautilus, etc.

Pila(snail)



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