350 Mottier. — The Effect of 
ment did not always take place, especially in longer pieces in 
which recovery was less rapid. The pieces of filaments almost 
invariably grew in length, thereby creating more space and 
a movement of the contents in the direction of growth. 
When such was the case, the proximal end of the filament 
remaining colourless would die after a time, and be cut off 
from the rest by a transverse membrane as in normal vegeta- 
tive propagation. 
It sometimes occurred that the ends of the filaments 
became thick and club-shaped, apparently as a result of 
the pressure exerted by the displaced contents. Further 
growth at such club-shaped ends manifested itself in a pro- 
longation possessing the normal diameter of the filament, 
which sprang usually a little to one side of the middle point 
of the end. 
Further experiments were made regarding the behaviour 
of oil-globules and bodies containing this substance in which 
leaves of certain Jungermanniaceae and root-tips of Ricinus 
were used. 
In cells of the leaves of the Liverworts, some of the bodies 
containing oil were displaced along with the chloroplasts, but 
not so readily as the latter, while many others remained 
stationary. It will be remembered, however, that these bodies 
do not represent pure fatty oil but contain more or less 
proteid, which makes them heavier than pure oil. 
Root-tips of Ricinus, having been subjected to the centri- 
fugal force, were immediately fixed in a mixture of chromic- 
osmic-acetic acid, imbedded in paraffin, and sectioned. The 
oil-globules are blackened by the osmic acid, so that they may 
be readily seen after the sections have been carefully stained 
and mounted in balsam. The proper combination of these 
acids must be used, or else the blackening may disappear, 
owing to oxidation caused by the action of the chromic acid. 
Here the results were about what would be expected. The 
oil-bodies, being lighter, were completely separated from the 
other constituents of the cell. The nucleus, small starch- 
grains, and the bulk of the cytoplasm were accumulated in the 
