THE CHEMICAL-COMPOSITION OF UPPER CARBONIFEROUS PTERIDOSPERM CUTICLES

Microscopically well-preserved leaf cuticles from four Upper Carbonife rous pteridosperm (seed fern) genera have been analyzed using solid st ate C-13 NMR and Curie-point pyrolysis. The chemical analyses reveal t he presence of highly aliphatic macromolecules, comparable with cutan. Cutan production is considered to be responsible for the preservation of these plant structures, and hence for the abundance of well-preser ved medullosan pteridosperm foliage in the Upper Carboniferous. Based on a comparison of data from the literature, and these new results, it is suggested that the resistant constituents of these cuticles may se rve as an additional source for n-alkanes on diagenesis and catagenesi s.