The mango is an example of a tree in which all the leaves on a shoot develop simultaneously instead of sequentially. The growth in area of all the leaves in a flush was followed at daily intervals. The dry weight, ash weight, water content, relative turgidity and rigidity of the leaves were measured at weekly intervals for the first 6 weeks of their life. They grew by cell division for the first 7 days after the fall of the bud scales and by cell enlargement over the next 7 days. Between day 7 and day 14 the dry weight per unit leaf area fell, the water content per unit leaf area increased, and the leaf became less rigid, finally hanging limply. After this date these trends were reversed. It is shown that the limpness of the young mature leaves is not due to lack of turgor, but may be correlated with a minimal value of the dry weight per unit leaf area.