1°40 
As I?) have previously described, the cytoplasm in Spirogyra 
possesses an alveolar structure. The hyaloplasm forms the walls of 
the alveoli, which are filled with a watery solution. By the action 
of reagents the structure is destroyed without the immediate onset 
of death. Often the hyaloplasm is seen to form a wall, which 
separates different portions of the contents. If abnormal plas- 
molysis is produced with, for example, 10°/, potassium-nitrate solu- 
tion then the hyaloplasm forms a wall round the contracted vacuole. 
As I*) have previously stated, it may not be assumed that this 
wall is a special organ and accurately represents that part of the 
protoplast which in the cell constitutes the lining of the vacuole. 
If dilute chloral-hydrate or phenol solutions act on the living 
cells, other phenomena are again observed *). .Cytoplasm collects 
round the nucleus and, taking up water, forms a vesicle whose 
wall again consists of hyaloplasm and whose content except for the 
nucleus is chiefly an aqueous solution. Smaller vesicles are formed 
on the suspensory threads. 
If instead of the last mentioned solutions a 5 °/, solution of ether 
(5 parts by weight of ether and 95 parts by weight of distilled 
water or ditch water) is used, then the death of the protoplasts is 
accompanied by the following phenomena. Cytoplasm flows towards 
the nucleus and collects there; the suspensory-threads are detached 
and are taken up by the protoplasmic mass, which has a granular 
appearance; round the nucleus a vesicle forms, which les quite free 
in the cell sap. The wall of the vesicle is again composed of a 
hyaloplasmie layer; the nucleus is seen lying inside the vesicle and 
between the protoplasmic wall of the vesicle and the nucleus there 
is an aqueous solution, in which some granules can be distinguished. 
The protoplasmic wall is at first fluid ard 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” separated; 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. 
It is otherwise when the content of the vesicle and the cell-sap 
1) CG. van WIssELINGH, Zur Physiologie der Spirogyrazelle. Beih. zum Botan. 
Centralblatt. Bd. XXIV (1908). Abt. I. S. 190 ff. 
2) Le. p. 185 ff and 192 ff. 
5) GQ. vAN WISSELINGH, Untersuchungen über Spirogyra. Botan. Zeitung. 1902. 
Heft. VE STAEN 
