Abstract
By incorporating 3H-thymidine to the meristematic root tips of Vicia faba and Narcissus jonquilla followed by trypsin digestion, it was revealed that the silver grains were arranged in a network pattern in the isolated interphase nuclei. In the metaphase chromosomes the grains were found to be localized along the digested chromatids and their number showed no significant difference from one longitudinal split to the other found within the same chromosome.
