Copyright. Papers accepted become the copyright of the journal (© 1991 The Royal Microscopical Society). Authorization to photocopy for internal or personal use or the internal or personal use of specific clients is granted by The Royal Microscopical Society for libraries and other users registered with the Copyright Clearance Centre (CCC) Transactional Reporting Service, provided that the stated base fee of $5.00 per copy is paid directly to the CCC, 27 Congress Street, Salem, MA 01970, U.S.A. This consent does not extend to other kinds of copying, such as copying for general distribution, for advertising or promotional purposes, for creating new collective works, or for resale. Special requests should be addressed to the Editor. 0022-2720/91 $5.00. Contents of Vol. 164 Part 1 SALVATORE LANZAVECCHIA, PIER LUIGI BELLON and BJORN A. AFZELIUS. A strategy for the reconstruction of structures possessing axial symmetry: sectioned axonemes in sperm flagella ZHIFENG SHAO, OTTO BAUMANN and ANDREW P. SOMLYo. Axial resolution of confocal microscopes with parallel-beam detection E. B. JENSEN and F. B. SORENSEN. A note on stereological estimation of the volume-weighted second moment of particle volume WALLY H. MULLER, THEO P. VAN DER KRIFT, GERD KNOLL, ERIK B. SMAAL and ARIE J. VERKLEIJ. A preparation method of specimens of the fungus Penicillium chrysogenum for ultrastructural and immuno-electron microscopical studies JoHN T. JONES and IoLto Ap Gwynn. A method for rapid fixation and dehydration of nematode tissue for transmission electron microscopy REINHARD H. DENNIN and AXEL BEYER. Application of scanning electron microscopy (SEM) and microbead techniques to study the localization of p24 and p18 antigens of HIV-1 on the surface of HIV-1-infected H9-lymphocytes B. BARBARA CZABAN and ARTHUR Forer. Visualization of ultraviolet microbeam irradiation sites with uranyl acetate T.A. HALL. Suggestions for the quantitative X-ray microanalysis of thin sections of frozen-dried and embedded biological tissues P. E. FROEHLING. A comparison of some methods for measuring the size distribution of two-dimensionally clustered latex particles in TEM images using mathematical morphology Short Technical Note CORNELIU DIMITRIU. On the contraction and dilation of the plastic support membranes under electron-beam irradiation in the transmission electron micro- scope Part 2 M. Driocratuti1, A. MOLINARI, A. CALCABRINI and G. ARANCIA. Electron energy- loss spectroscopy analysis of adriamycin—plasma membrane interaction A. N. Far ey and J. S. SHAH. High-pressure scanning electron microscopy of insulating materials: a new approach D. J. GOLDSTEIN. Quantitative theory of ideal phase-contrast microscopy, taking object width into account EISAKU OHO, AKINORI OGIHARA and KOICHI KANAYA. A method using an on-line digital computer for the improvement of resolution of backscattered electron images Monty Gtass and T1mM Dasss. The experimental effect of detector size on confocal lateral resolution DIETRICH STOYAN and VICTOR BENES. Anisotropy analysis for particle systems PavEL E. Moroz. Microscopy of cell cultures through thin plastic films Short Technical Note LAuRA RIBONI and HAROL NUNEZ-DuRAN. A device to ease grid coating for EM radiography Book Reviews Erratum Part 3 Editorial D. A. WHARTON. Freeze-substitution techniques for preparing nematodes for scanning electron microscopy STEPHEN S. CAMPBELL, BRUCE J. CRAWFORD and COoRINNE L. REIMER. A simple ethanol-based freeze-substitution technique for marine invertebrate embryos which allows retention of antigenicity TIMOTHY J. HOLMEs, YI-Hwa Liu, DEEPAK KHOSLA and Davip A. AGARD. Increased depth of field and stereo pairs of fluorescence micrographs via inverse filtering and maximum likelihood estimation Eric Q. CHEN, CHAN F. LAM and AMMAFI PERIASAMY. Effect of refraction on optical microscopic measurement of internal blood-vessel diameter and its correction FLEMMING @. MATHIASEN, HANS JORGEN G. GUNDERSEN, ARVID B. MAUNSBACH and ELISABETH SKRIVER. Surface areas of basolateral membranes in renal distal tubules estimated by vertical sections Short Technical Note J. C. Ottvo, E. KAHN, S. HALPERN and P. FRraGu. Image registration and distortion correction in ion microscopy Book Reviews