Growth of the Dandelion Scape.

The growth of the flowering stalk of dandelion, Taraxacuwm officiiwle, is of considerable interest because of the presence of two distinct periods of rapid growth. The last of these precedes and accompanies the maturation of the fruit, and represents a resumption of rapid growth in what would normally be considered a mature organ. MIYAKE (8, 9) showed that growth of the dandelion scape may be divided into three phases: the first a fairly rapid, uniform growth, the second a phase of slow growth; and the third, a rapid growth in the upper portions of the organ. SCHmALFUSZ (10) showed that mitotic figures were present in elongating scapes up to the stage of shedding ripe fruits and were especially frequent preceding the periods of greatest scape elongation. As a part of a general study of the mechanism of cell elongation the experiments of MIYAKE and SCHmALFuSZ have been repeated and extended. The data presented were obtained from extensive studies of the regions and periods of cell division and elongation in the dandelion scape, together with studies of cell volume, green and dry weight, and nitrogen content on a per cell basis. Cell division and enlargement