74 M. Miller on the Formation of Starch. 
investigation. Some time elapsed before this opportunity occurred. 
In the interval the young Chare had become rapidly decomposed 
and agglomerated, the fruit alone preserving its form. When 
some of this was placed under the microscope, not only were the 
contents of the spiral sacs of the spores decomposed, but the sac 
itself could now easily be dissolved from the nucleus, so that the 
latter emptied itself of its cells on a little dissection with a knife. 
I then perceived what [ had so long sought for m vain. All the 
progressive stages of the later cell-development were exposed to 
view, so that the formation of the starch-granules could be 
readily perceived by the action of tincture of iodine. The entire 
result,—the whole mystery of the formation of starch, may be 
expressed in very few words: it ts the eytoblasts which are trans- 
formed into starch, and this occurs in the mature cells only. 
If there is only one cytoblast im a cell, and this does not con- 
tain any further cytoblastema, the cytoblast becomes simply ex- 
panded in all directions until it has reached the circumference of 
the cell-membrane which surrounds it. It then exhibits an ex- 
tremely thick dark outline, whence we may conclude that its 
membrane is tolerably thick. At the same time it is not perfectly 
homogeneous, but of a granular structure. But when the out- 
line of the other hemisphere which lies beneath it is examined 
at the same time, it may be most distinctly perceived that the 
cytoblast is hollow. This is particularly well seen when it has been 
coloured very pale blue by tincture of iodine. At the same time 
we generally perceive within the cytoblasts some more or less 
roundish and more or less curved granules. ‘This is the simplest 
case. 
The formation must necessarily become more complex, when 
in addition to the cytoblast, which is hollowed out and has be- 
come converted into starch, several other cytoblasts occur. If 
this happen, the membrane of the primary cell generally becomes 
very thick in some places, 7. e. a granular mass has been depo- 
sited upon it, which must be considered as cytoblastema, because 
its structure is of the same granular kind as that of the other 
parts of Chara (for instance, the cytoblastema between every two 
cells, from which new cells are formed, consequently in interca- 
lary growth) and is coloured yellow by iodine. In this mass some 
portions are heaped up, forming one or several more or less glo- 
bular groups which become expanded and hollow. They are ey- 
toblasts which do not however form any solid membrane on their 
surface, which by its expansion might enlarge so as to form a ho- 
mogeneous vesicle, as ordinarily occurs in the process of cell- 
formation. Thus whilst in the latter case a thin layer of the cy- 
toblast dilates into a homogeneous membrane, in the former the 
whole mass of the cytoblast is expanded, whence it must neces- 
