Electron micrographs of spores of some British gasteromycetes

Spores of some British Gasteromycetes have been examined with the electron microscope. The increased resolving power and great depth of focus enable details of the surface ornamentation to be studied, but the low penetrating power of the 50 kV. electrons used does not permit any internal structures to be seen. The spores of some species which were previously described as smooth are shown to be warted, and the warts on all species examined appear to conform to the same basic pattern. This consists of a low truncated cone having an angle of 45–70° capped by a much flatter cone, the shape of which varies among the different species. To account for the formation and shape of the warts, and also for the presence of circular disks about 0·2 μ diameter, sometimes observed in mounts from immature specimens, it is suggested that, during the disintegration of the gleba, the spores are coated with a gelatinous film which shrinks and cracks while drying.