1. Very conspicuous and persistent nucleoli conducting in a peculiar manner in the course of karyokinesis were found in the roottips of some thirty species and cultivated forms of Phanerogams. 2. Those plants which possess such nucleoli show several other karyological peculiarities in common. 3. Though the morphological behaviours of these nucleoli seem to favour in general the transportation theory of nucleolus, the karyotin contents of nucleolus could not be verified microchemically. 4. The nucleolus in general can easily be distinguished in microchemical way from chromosomes.