Archerd Shell Collection > Shell Classes > Mid-Section of Shell

Mid-Sectioned Gastropod Shell 


(Left) The shell of the tun mollusc, Tonna perdix, shows a rather beautiful architecture when cross-sectioned vertically, near the midline. While this is a rather delicate shell, the structure is nevertheless typical of many gastropod shells.

Note the vertical column, or columella, formed by twisting of the shell as the snail grows. A particularly large aperture at the opening of the final whorl is characteristic of the tun family (Tonnidae)

(Modified picture, from Wilson & Gillett, 1971)


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Archerd Shell Collection > Shell Classes >Mid-Section of Shell