Introduction
A sea shell is a surface in 3-space which can be thought of as resulting from the motion of a generating curve along a structural curve. The latter describes the global shape of the shell while the former models the shape of the shell aperture. In what follows, we introduce a 13-parameter model of sea shells, based on [1]. The equations we use are a slight modification of those presented in [1]. A computer program, written in MATLAB, is available to plot some special shells or to design new ones. The parameters values for special models of shells are taken from [1] and [2].
1. M.B. Cortie, Models for mollusc shell shape, S. Afr. J. Sci. 85, 454-460 (1989).
2. M.B. Cortie, Modelling the surface bumps and spikes of molluscan shells, in the Proceedings of the First International Conchology Conference, Edited by C.R. Illert, Hadronic Press, Palm Harbor, 1995; pp. 46-65.