Treated with 10% NaOH so radular sac and cuticle of odontophore dissolved away. Proximal end of radular ribbon uncoloured as teeth formation just begun. Colour of teeth darkens towards odontophore at anterior as they develop and accumulate hard, golden mineral (probably of iron). In life, radula looped to and fro among viscera to fit inside body. On odontophore, radula rests in groove between left and right cartilages.

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