THE VARIATION IN CELL LENGTH WITHIN ONE GROWTH RING OF CERTAIN ANGIOSPERMS AND GYMNOSPERMS

Abstract
The variation in cell length within one growth ring at the one level has been studied in 28 angiosperme and 8 gymnosperms. In those angiosperms with distinct growth rings a definite increase in fibre length has been found from the first-formed early wood to the last-formed late wood within the one growth ring; in species without definite growth rings little or no variation in fibre length has been observed over radial distances covering the growth of several years. The relationship between these changes in cell length and growing conditions has been discussed. In gymnosperms a slight but definite increase in tracheid length from early wood to late wood was noted in most cases. Where compression wood was present a definite drop in tracheid length occurred.