Phragmites communis, Eriophorum vaginatum, Calluna vulgaris, and Sphagnum palustre are representative of plants whose remains are frequently encountered in Scottish peat deposits. The effects of preservation in peat on the surface features of their leaves were followed by electron microscopy. Wax projections were observed on the surfaces of mature living leaves of Phragmites and Eriophorum but not on Calluna or Sphagnum. Details of cell wall outlines and stomata (or pores) were clearly defined in Phragmites, Eriophorum, and Sphagnum, but obscured in Calluna. The previous year's leaves differed by displaying a general absence of wax projections, an erosion of the cuticular surface, which took the form of either a loss in definition of the cell wall outlines or a definite etching of the surface, and the presence of numerous microorganisms. The surface features of preserved leaves exhibited to a greater degree this erosion of cell wall outline and cuticular surface. This preliminary study has indicated that major alterations in the submicroscopic features of cuticularized leaf surfaces occur at the leaf litter stage. The primary agents responsible for this degradation would appear to be microorganisms in conjunction with the physical and chemical processes of peat formation.
