51 
stretched. When the protoplast dies, this changes; the 
protoplasmic-wall becomes rigid and often acquires folds 
and creases. The nuclear-wall also, which is stretched as 
long as the protoplast lives, contracts irregularly. By the 
walls different fluids are at first sepa- 
rated; this also is changed by death. 
When the nuclear wall contracts, we 
may assume that its content comes 
into contact with that of the vesicle, 
but this is not accompanied by any 
noticeable phenomenon. Ît is other- 
wise when the content of the vesicle 
and the cell-sap come into contact. 
This takes place at one or more points 
on the circumference of the visicle. 
At these points precipitates are produ- 
ced, but it cannot be seen whether 
at first small openings or tears occur 
in the vesicle. It is often possible to 
distinguish two parts in the precipitates: 
the one is compact and seems to lie 
| within the vesicle; the other is looser 
Vesicles round the nu- ; 
and occurs outside the wall of the 
cleus with precipitates of 
protein and tannin. latter. 
When the precipitates are investiga- 
ted with reagents, they are found to consist of protein and tan- 
nin. With sugar-solution and 851/,°/, sulphuric acid they 
become very distinctly red, especially the more compact por- 
tion; after treatment withiodine in potassium iodidesolution and 
washing out with water they show a reddish violet colour. 
With ferric acetate they become blue-black, with potassium 
bichromate brownish-red. 
From these results 1 think the following conclusions may 
be deduced. The vesicle contains a solution of protein, 
which is derived from the cytoplasm and probably occurs 
