52 : BOTANICAL GAZETTE [JANUARY 
EXPLANATION OF PLATES III AND IV. 
The figures were drawn with the aid of an Abbé camera. 
PLATE III. 
Fic. 1. Daughter nucleus from a cell -where the cell plate is not yet com- 
pleted. The nuclear structures in this cell retained the eosin stain, the pyrenoids 
black from haematoxylin. x 1750. 
Fic. 2a. Nucleus preparing to divide, showing growth of bodies in the periph- 
eral network before breaking up of the central body. Pyrenoids and nuclear 
structures in this cell retained only the eosin stain. 1750. 
uclear material stained black by the haematoxylin, all the chro- 
matic material being apparently condensed in the ee occupied by the central 
body. X 1750. 
. Fic. 3. Nucleus showing the breaking up of chromatin body and increase 
in size of the peripheral bodies. The pyrenoids retained the eosin stain; all the 
nuclear structures are stained black, several of them somewhat darker than the 
others. X 1750. 
IG. 4. Nucleus showing the beginning of the massing of the chromosomes, 
the nuclear membrane as yet undissolved, the granules in the region of the cell 
plate formation being conspicuous. Chromosomes black, pyrenoids red 
Fic. 5. Later stage, showing the clearing of the nuclear interior, recalling the 
synapsis stage described in higher plants. Pyrenoids red, several chromosomes 
black, remainder red. X 1 
Fic. 6. Similar stage, very frequent; chromosomes numerous, massed 
together, all stained red. 1750. 
Fics. 7, 8. Similar stages where there is no massing of the chromosomes. 
In 7, a chromosomes were stained black, others red. In 8 those stained black 
are grouped in one corner of the nucleus, those red are scattered. 1750. 
Fic 9. A stage where distinct lines of granules connect chromosomes with 
nuclear membrane. Four chromosomes black, others red. X 1750. 
Fic. to. A rare stage with numerous chromosomes arranged in circle within 
the sitenk before the nuclear membrane becomes dissolved. All chromosomes 
lack. X 1750. 
_ Fic. 11. Another rare stage; nuclear membrane dissolved, remains of central 
body still in the cytoplasm, retaining a lighter eosin stain than the other chro- 
mosomes. X 1750. 
Fics. 12, 13. Two adjoining cells in same filament showing disparity in 
size and number of chromosomes. Pyrenoids red, in fig. 12 chromosomes stained 
sere by haematoxylin; in fig. 13 nuclear structures stained red. The line 
of granules marking the region of cell plate formation shown in both figures. 
x1 
Fic. 14. All chromosomes black, but some drawn lighter to indicate that 
they were lying in three different planes. x 2440. 
Fic. 15. Chromosomes black, showing indefinite arrangement as hey are 
being drawn to the center. 2440. 
