Samples were taken from dry seeds of radish and fixed in glutaraldehyde. Ultrathin sections were observed without contrasting treatment. From cotyledonary parenchyma, it was possible to obtain powders or prints, which were observed by transmission electron microscopy. They showed several types of crystals. In the ultrathin sections of parenchyma cells, the crystals are included in globoids. Electron probe microanalysis with a wavelength dispersive spectrometer (Camebax microprobe) showed that they were rich in P, Ca, and Mg. In the powders and the prints, several polymorphic crystals, of varied sizes, were observed; these were sensitive to the electron beam. Some have relatively high ratios in Ca, lower ratios of S, and other elements, such as Si. Others possessed high ratios of Si with other elements, such as Ca and Al. The latter were less dense, more stable under the beam and their average diameter was smaller. Other crystals were smaller (some tenths of a micrometre). They were electron dense and very stable. Some of these were rich in Fe and could contain other elements (among others Si, Ca and P).
