Center: One-liter Erlenmeyer flask of Vibrio fischeri grown on PB (Photobacterium) broth and exhibiting bioluminescence. The culture was prepared by Sandra Dunbar and the photograph made by Farid Hemmati using a Minolta X-300 camera with a Tamron 35–80 zoom lens. See article by Hoffmann et al., this issue, pp. 41–47, on “Combination ecotoxicity and testing of common chemical discharges to sewer using the Vibrio fischeri luminescence bioassay”.

Upper left: Three dimensional reconstruction of the Infectious Bursal Disease Virus (IBDV), from chicken, obtained by image processing from cryo-electron micrographs of purified virions. The resolution is 2.8 nm. Authors: José Ruiz Caston, Francisco Rodríguez and José L. Carrascosa, National Center for Biotechnology, CSIC-UAM, Madrid, Spain. (Magnification, ca. 1,300,000×)

Upper right: The bacterial community at the sediment–water interface of a stratified lake (Burke Lake, in the Rose Lake recreation area, near East Lansing, Michigan). Phase micrograph by Douglas E. Caldwell, University of Saskatchewan, Canada. (Magnification, ca. 1100×)

Lower left: The wood-digesting symbiotic protist Joenia annectens from the European dry wood-esting termite Kalotermes flavicollis. Phase contrast image by Michael Dolan, University of Massachusetts at Amherst, USA. (Magnification, ca. 3100×)

Lower right: Histoplasma capsulatum FMR6518. Mature macroconidium with club-shaped ornamentation. Scanning electron micrograph by J. Gené and M. J. Figueras, University Rovira Virgili, Reus, Spain. (Magnification, ca. 5300×)