involute Having edges that roll under or inwards. Applied to those coiled cephalopods (Cephalopoda) where the final whorl of the shell envelops earlier ones. The opposite of involute is evolute, where all the previous whorls are exposed. The term ‘serpenticone’ is sometimes applied to those evolute cephalopods where the shell resembles a coiled snake. Very laterally compressed shells (discus-shaped) are called ‘oxycones’; very flat and inflated types are called ‘cadicones’; those which are subspherical are called ‘sphaericones’.

involute Having edges that roll under or inwards. Applied, for example, to coiled cephalopods (Cephalopoda) in which the final whorl envelops earlier ones.

involute Rolled inward, e.g. of a leaf. Compare EVOLUTE.