262 GOLDSTEIN: PLANTS AFFECTED WITH Mosaic DISEASE 
tact with the nucleus. It is densely granular and contains 
several small vacuoles. Careful and prolonged observation of 
such bodies shows that they undergo slow changes in position 
and sometimes of form. The contents seem sometimes to Le- 
come more vacuolar. This body closely resembles the bodies 
found in sectioned and stained material, as in figures 7 and 8, 
in its irregularly lobed or oval outline, in its compact granular 
structure, and in the presence of one or more vacuoles. Bodies 
of this kind can be seen in almost every cell of a bit of epidermal 
tissue stripped from the yellow area of the midrib or leaf blade. 
Such bodies as this shown in figure 1 are not the result 
of nuclear fragmentation or direct nuclear division as Iwanowski 
first suggests. From his figures and mine, it is clearly evident 
that the finely granular and rounded nucleus could not be frag- 
menting or giving rise by direct division to daughter nuclei. 
They do not represent migrated nuclei such as Miehe ob- 
served in stripped off epidermal tissue of Tradescantia stems and 
leaves of Allium. Miehe found the nuclei that had migrated 
through the cell walls into adjacent cells showed exactly the 
same finely granular content as did the original nucleus of the cell. 
I have also attempted to stain preparations containing such 
cells as shown in figure 1, with various intra-vitam nuclear 
stains. I have obtained the best results with thionin. Ina drop 
of water placed against the edge of the cover glass, a grain of the 
stain was dropped. This gradually dissolved and the violet 
color slowly diffused under the cover glass.. The nucleus of the 
cell takes a lavender tint, while the nucleole stains violet. The 
X body does not take the stain as a whole but its granules seem’ 
to become more clearly differentiated. 
In figure 2, the nucleus is shown, as is frequently the case, 
suspended in the cell by fine cytoplasmic threads in which 
active streaming is going on. In this cell five X bodies are lying 
about the nucleus. Within the bodies themselves, active motion 
of granules, amounting almost to circulation, was conspicuous. 
All five of these bodies were slowly rotating and at the same 
time gradually changing their positions in the cell. During the 
several hours in which this cell was under observation, the 
bodies moved up and down the cell for considerable distances, 
continually changing their positions relative to the nucleus and 
to each other. 
