Article: Transmission electron microscopy of fossil spores

Transmission electron microscopy of fossil spores presents special difficulties. A major problem in megaspores is obtaining low power pictures of whole spores; this is overcome by using single-hole discs instead of grids. Care is needed to avoid damaging sporoderm ultrastructure by oxidation during preparation. Results achieved since 1965 are reviewed, and the sporoderm fine structures of Setosisporites (Carboniferous) as well as Salvinia and Alnus (both Tertiary) are illustrated and interpreted.