76 BOTANICAL GAZETTE | AUGUST 
that the granules of the cell plate react as albumen. As to the 
origin of these granules it was observed that they are not added 
from the surrounding protoplasm but are within the fibers them 
selves. The fibers appear as if made up of small granules. These 
granules are really contained in the fibers as if in tubes, and they 
collect at the equator, forming apparent equatorial swellings af 
the fibers, z. ¢., the cell plate elements. The cell plate elements, — 
after growing by the addition of new granules, finally fuse intoa 
continuous plate. 
In 1887 Went® showed that connecting fibers and other 
spindle fibers are identical, and that the former apparently 
increase in number before the cell plate appears. He was not able, 
however, to account for the origin of the new fibers. Prior to the 
formation of the cell plate, Went observed a stained substance 
between the fibers of the connecting spindle next to the daugh- 
ter nuclei, leaving thus a clear zone in the equator of the spindle. 
This stained substance was thought to be nucleolar matter dis- 
solved in the nuclear sap. Inthe subsequent stages these two 
darker zones move to the equator where the cell plate is built. 
Its origin Went did not see, but he showed that its growth® 
peripheral, as had been well established by previous observels: 
Went, however, observed for the first time that the connecting | 
fibers disappear in the center of the spindle during the gro ol 
of the cell plate, so that the peripheral fibers form a ring -_ 
nected with the growing region of the plate. 
Opposed to the view of Strasburger as to the cytoplasm 
origin of the cell plate by fusion of swellings of the connectitt 
fibers, was that of Zacharias, who contended that the spines 
is of nuclear and the cell plate of cytoplasmic origin, thus fol 
lowing Treub’s theory of the origin of the cell plate from oe. 
granules. The cell plate is formed by the entrance of substal | 
from the surrounding protoplasm into the equatorial region of the 
central spindle, which is a portion of the dividing nucl ye 
ee Beobachtungen iiber Kern u, Zelltheilung. Ber. d. deutschen botan. Ges. - 
° Ueber Kern u. Zelltheilung. Botanische Zeitung 46: 56. 1888. 
