BIHANG TILL K. SV. VET: AKADSHANDL. BAND: (9: N:0 3. 11 
chlorophyllaceous bands occur also in cells which have already 
attaimed their definite length. In one of the cells belonging 
to the filament represented fig. 1, about a third part of the 
chlorophyllaceous band turned 90 degrees around its longi- 
tudinal axis, but resumed its original position within a short 
time, not to mention other similar instances. Whether such 
movements of the chlorophyllaceous body of the vegetative 
cells occurs also in other Mesocarpee, 18 not known. It seems 
however probable; and this circumstance may be worth ob- 
serving by those who can obtain fit material for investigation. 
— Gonatomena ventricosum thus gives a second in- 
stance of independent movements of chlorophylla- 
ceous bodies belonging to vegetative!) cells. The 
first instance has very lately been made known by Dr. W. 
VELTEN ”), who has drawn attention to the free motion of the 
chlorophyllaceous granules in two species of the genus Charu. 
The formation of vegetative cells in Gonotonema ventri- 
cosum takes place by bipartition exactly in the same manner 
as in the rest of the Mesocarpew. We may therefore let this 
alone, and pass to an account of the manner of the formation 
of spores. The cells destined to bring forth spores have al- 
ways a very considerable development as to length. While 
the vegetative cells just formed by bipartition are only 5—6 
times as long as thick, the cells which are ready to form 
spores are at least 9 and more often 12—16 times as long as 
thick. A rather considerable increase as to volume, by deve- 
lopment in length, does consequently take place in these 
cells, before they are capable of fulfilling their propagative 
purpose. . 
The first sion of a beginning spore-formation is that the 
cell widens at its middle, so that this part resembles a cask. 
This widening is not, however, equally powerful on all sides, 
but is stronger on one side than on the other sides. At the 
same time the cell bends at its middle like a knee, so that 
its two halves form a more or less obtuse angle with each 
other; see fig. 4a. The point of the angle is placed where 
the before mentioned more powerful widening of the cell has 
taken place. Almost always the formation of spores takes place 
') On the movements of the chlorophyllaceous bodies in the conjugating 
cells, see below in this treatise. 
?) In Oesterreichische Botanische Zeitschrift. 26 Jahrgang. N:o 3. 1876. 
