In light of the structural and dielec. data available for 23 boracites, a phenomenol. approach of the sequences of ferroelec.-ferroelastic phases obsd. in this family of compds. is proposed. It makes use of a single 6-dimensional order-parameter, in agreement with the theory of V. Dvorak and J. Petzelt (1971) and Yu. M. Gufan and V. P. Sakhnenko (1973) and in contrast to the 2-order-parameter model claimed by A. P. Levanyuk and D. G. Sannikov (1974, 5). A new interpretation is suggested for the temp. dependences of the polarization and dielec. permittivity, which involves 2 coupling terms, linear in the polarization components, and resp. quadratic and cubic in the order-parameter components.