STATUS OF VOLUME A: SPACE-GROUP SYMMETRY Th. Hahn, Institut fuer Kristallographie, Rheinisch-Westfaelische Technische Hochschule, D-52056 Aachen, Germany.

The Fourth, revised Edition of Volume A of International Tables for Crystallography was published in the spring of 1995. A corrected reprint of this edition is presently in the press.Two new features are noteworthly for the fourth edition:

(i) Completion of the space-group-diagram project: all 17 plane groups and 230 space groups now contain new diagrams; also the explanatory diagrams in Section 2.6 were newly done. Special attention is drawn to some new features of the cubic diagrams for which examples will be given.

(ii) In accordance with a recent Nomenclature Report of the IUCr [de Wolff et al., Acta Cryst. (1992). A 48, 727-732] the new graphical symbol .._- .._- for "double" glide planes e oriented "normal" and "inclined" to the plane of projection has been incorporated in 17 centred orthorhombic, tetragonal, and cubic space-groups. The introduction of the glide plane e leads to new symbols for the following five space-groups:

Space-group No. 39 41 64 67 68

Present symbol Abm2 Aba2 Cmca Cmma Ccca

New symbol Aem2 Aea2 Cmce Cmme Ccce.

The implications of these new symbols will be explained.