Division in the Root of Vicia Faba. 169 
solved by the action of the cytoplasm or dispersed through 
the latter, so that no remnant is found in the region of the 
spindle or of the chromosomes. During the time the 
nucleolar substance is disappearing, the chromatin stains red 
with eosin and this the author says may be explained by the 
assumption that the nucleolar substance either unites chemi- 
cally with the chromatin or penetrates into the meshes of the 
latter. There is, however, no chemical union with the 
chromatin and, therefore, the chromosomes probably do not 
serve to carry it over to the daughter nuclei. 
There are only a few observations which would show that 
the chromosomes are derived from nucleoli. But most 
observers agree that the nucleoli disappear more or less during 
mitosis, and that the chromosomes are not derived from them. 
As to the mode of transference of nucleolar substance to the 
daughter nuclei, the author concludes that it is different in 
different objects. In most cases, the nucleolus disappears. 
Wager suggests that the chromosomes serve for mechanical 
vehicles of transportation. Or the nucleolus may become 
dispersed in the cytoplasm after the nuclear membrane has 
disappeared and that each daughter nucleus may take up 
substance from the cytoplasm or produce its own nucleolus 
from new substance. 
Function of the Nucleolus.—As a relatively large amount 
of nucleolar substance is found in the growing nuclei, the 
author concludes that it stands in some connection with the 
process of nutrition, is either itself nutritive or represents that 
portion of the nucleus from which all the nutritive material 
thas been extracted, z. ¢., it is a waste product. Or it may 
represent accumulations of nutritive material retained in the 
nucleus as a reserve supply—this last is not very probable. 
Dr. Montgomery suggests the hypothesis that the nucleolus 
may arise as a functionless inert mass and acquire its activity 
later. But in all cases the nucleolus would seem to be in 
