Difference in the Behaviour of Tissues in Ancient Plant Remains and during Chemical Treatment

ALTHOUGH considerable work has been done on the cell wall structures of ancient and buried woods 1 and their degradation 2 from chemical, physical and botanical aspects 3 , little attention has so far been paid to the differential behaviour of the main tissues of such woods. While studying the minute anatomy of fossil woods and buried woods, we noted the peculiar behaviour of the two important tissues of the dicotyledonous woods. During long submersion of wood in water or soil, parenchyma cells and rays are usually found to retain their original structure better than the fibres (Fig. 1). This was reported by two of us (K. A. C. and S. S. G.), but no definite reason for such behaviour could be put forward except the nature of pits on the walls of fibres, vertical parenchyma cells and wood rays 4 . The main obstacle to chemical investigation has so far been the difficulty of obtaining pure samples of parenchyma and fibres from fresh woods. Recently, while working on bamboo, it has been possible to separate mechanically its parenchymatous and prosenchymatous tissues. This led us to think that it might be worth while analysing chemically these pure tissues and at the same time examining them microscopically at different stages of delignification, with the view of getting a clearer picture of the nature of the cell wall.