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In one day, but this is always accompanied by a great loss of proto- 
plasm by which the cell is much enfeebled. 
This time I succeeded in finding a new method in order to get at the 
same result, based on the observation that every laceration of a 
part of the numberless protoplasm-threads, which run through the 
whole plant as an extremely fine network, is immediately followed 
by the loeal secretion of a white, tough, wiry substance, which very 
soon becomes stiffer, assumes a bright yellow colour and then forms 
a perfect partition. If at the same time the cell-wall had been injured, 
the external wound is closed in this way. But the same laceration 
of the plasm-threads can be brought about by pressure and without 
external lesion; the partition is then restricted to the place where 
sufficient pressure was exerted. In this manner one can at any 
arbitrary point of the leaf produce, as it were, a eross-wall, to which 
any desired direction and length can be given. If one proceeds with 
care this partition is no broader than */, millimetre. 
In this way one can also physiologically, namely without external 
lesion, divide a leaf into two or more parts. 
This treatment, which in all respects has the same consequences 
as are observed with a wound, is not accompanied by weakening of 
the cell, since no protoplasm is lost, and besides the plant is already 
after a minute fit for further manipulations or for examination. 
Caulerpa prolifera derives its specifie name from the circumstance 
that the “leaves” which spring forth from the “rhizome” very often 
produce new leaves, prolifications. Especially by this circumstance 
I succeeded formerly in showing that, in accordance with pm Vrins’ 
views, there exists also in this plant a direct relation between the 
intensity of the motion of the protoplasm in various places and that 
of the nutrition in these places. The bundles of protoplasm bands, 
coloured dark green by chlorophyl grains and very often visible to 
the naked eye, which pass from the stalk of the prolification into 
the primary leaf and then tend to the leaf-stalk of this latter were 
a very important aid in this investigation. 
These bundles are lacking where very young prolifications are 
found and only gradually develop in the leaf, and in doing so always 
begin at the stalk of the prolification and extend towards the base 
of the leaf. These stream-bundles are never seen developing in the 
opposite direction, i.e. beginning at the leaf-stalk and extending 
towards the stalk of the prolification, neither do they proceed from 
the prolification to the top of the leaf. So they originate from above 
and tend downward. 
Moreover if an existing prolification is cut off, one sees the bundles 
