1908] CURRENT LITERATURE 393 
had little effect on the size of the spores or hyphae; and that ammonium nitrate 
can be used to a limited extent as a source of nitrogen, but that it is rather poorer 
than ammonium tartrate-—F. L. STEVENS. 
The vegetative activity of chromatin.—DERSCHAU’S” results and theoretical 
views on the vegetative activity of chromatin are interesting. Many granular 
chromatin substances thrown out of the nucleus into the cytoplasm increase in 
size, assume spherical forms, and then, becoming oriented at the poles of spindle 
figure, function as centrosomes. This is regarded as the vegetative activity of 
the chromatin. His studies cover several forms of higher vascular plants, such 
as Fritillaria imperialis, Iris germanica, Vicia Faba, Lilium Martagon, Funkia 
steboldiana, and Osmunda regalis. From his investigation of the pollen mother 
cell and meristematic tissue of these forms, he concludes that there exist central 
ies in the mitotic figure of the fern and flowering plants which are of nuclear 
origin and are analogous to blepharophlasts. 
The following is a brief summary of his account. In very young mother cells 
of Lilium, Funkia, and Osmunda, chromatin is observed escaping from the 
nucleus in various spots. Outside the nucleus the chromatin substances increase 
in size and assume spherical forms. The spherical chromatin substances refract 
light and close examination of them seems to show a reticulated structure. With 
Stains they react like chromatin and linin. While the chromatin is escaping the 
nucleolus remains within, which shows that the substances thrown out are not 
nucleolar. In late prophase the spherical chromatin or ‘“‘Sphaere” seems loosened 
and differentiated into two structures, one the center and the other a single heavy 
ed fiber. Some of these centers make their way toward the Hautschicht 
during a later phase of mitosis and furnish the anchoring-place for the spindle; 
Some lie scattered in the cytoplasm; and still others remain near the nuclear per- 
phery. To each of these centers there is attached a single heavy beaded fiber, 
ftom which there seem to be spun out fine spindle fibers. Generally the spindle 
Start as multipolar polyarch, then become bipolar, but remain in the 
Polyarch condition until telophase; and therefore several centers persist without 
ion at each pole, each spindle cone being associated with a single center. In 
tafe Cases some of these centers fuse together to form a kinoplasmic plate, which 
S connected by beaded heavy fibers with other centers that remain separate. 
In telophase the central and mantle spindles again take on a beaded structure. 
The centers and fibers, instead of entering into the constitution of the organizing 
daughter nucleus, remain in the cytoplasm and undergo certain changes in the 
Stfucture. These centers at the pole of the spindle, DERSCHAU thinks, control 
- Mechanism of mitosis. He states further that the centers may be asdietsvagon 
allied to the blepharophlast, and are to be regarded as analogous with it, if not 
homologous; both lie near the nucleus, increase in volume, and mark the starting- 
Point of fibers—one of cilia and the other of spindle fibers SHIGEO YAMANOUCHI. 
he. ie Blepharophlasten. 
HAU, M. v., Beitrige zur pflanzlichen Mitose, Centren, Blep 
Jahrb, Wiss. Bot. 46: 103-118. pl. 6. 1908. 
