The meristematic cells of the roots of Vicia faba have been examined by ultraviolet absorption microscopy, by interference microscopy and by staining with methyl green both with and without prior treatment with deoxyribonuclease. The ultraviolet absorption of the nuclei is insufficient to account for more than about 15 per cent of the diploid amount of DNA known to be present in these cells; damage to the cytoplasmic granules results in the normal amount of DNA being located entirely in the nuclei. This change is also associated with an approximately two-fold increase in dry mass, and the nuclei become basophilic. Evidence is presented that, when perfectly preserved, the cytoplasmic granules contain DNA. It is suggested that the most likely explanation of these results is that at least most of the DNA of meristematic cells is present in the cytoplasm, associated with the granules which are peculiar to these cells. When the cytoplasmic organization is disrupted, or when the cells differentiate, the DNA diffuses into the nucleus.