Center: Free-living dinoflagellates of the genus Pyrocystis Murray ex Haeckel, 1890. Drawing by Edouard Chatton (1883–1947), Banyuls-sur-mer, France, for one of the numerous “class-boards” composed for his students (ca. 1930). The original size of these boards (the present figure is a part of one of them) is about 100 cm in width on 150 cm in height. See article by Soyer-Gobillard, MO, this issue pp. 37–42. (Magnification, ca. 900×)

Upper left: Human calicivirus (Norwalk-like virus). Transmission electron microscopy (negative staining with phosphotungstic acid) by David Cubitt, Great Ormond Street Hospital, London, and Albert Bosch, University of Barcelona, Spain. (Magnification, ca. 650,000×)

Upper right: Cross section of a high-pressure freezed and freezed substituted sample of cyanobacterium Halospirulina sp. Samples were frozen at high-pressure in a Leica EM Pact High-Pressure Freezer, and freeze-substituted at –90ºC for three days in a Leica AFS instrument (Xavier Huete, Jordi Urmeneta and Carmen López-Iglesias, University of Barcelona, Spain). (Magnification, ca. 35,000×)

Lower left: Nuclear and infraciliature features of the ciliated protozoa Colpoda inflata, observed by silver carbonate impregnation. This strain was isolated from a soil sample from Panama forest. Courtesy of Carmen Jareño and Ana Martín-González. University Complutense of Madrid, Spain. (Magnification, ca. 1000×)

Lower right: Basidia of Lentinula edodes. Scanning electron microscopy image of a fertile gill’s surface showing 4-sterigmated basidia, some with developing spores. The mushroom fruited at the Bank of Edible and Medicinal Mushroom (BEMF), University of Barcelona (http://www.ub.es/bemf) . (Magnification, ca. 4000×)