Serial sections 1·0 mm. in length taken from the tip towards the base of the bean root have been cultured on 2 per cent, sucrose. At various time-intervals, length, invertase, phosphatase, and protein content of the sections have been determined. Alterations in the enzyme complement of the sections have been related to growth and protein content. The relation of changes occurring in excised fragments to those in the intact root have been discussed.