1900] THE CELL PLATE IN HIGHER PLANTS 157 
growth is continuing, the older portion of the cell plate splits 
and the new wall is laid down between the halves. These 
processes continue until division is complete. During the 
period of growth the cell plate may so shift its position as to lie 
ina plane different from that in which it was first formed. 
I have thought it best to describe the above processes sepa- 
rately. The fate of the spindle fibers is a question of much 
interest here. From the phenomena that I have been able to: 
observe in the cells studied, I have become convinced that all 
of the fibers that form cell plate elements are completely used 
up in the growth of the cell plate. A comparison of figs. 4, 5+ 
6,and 7 is instructive on this point. In fig. g the cell plate 
elements have just formed, the connecting fibers have drawn 
away from the daughter nuclei, and granular trophoplasm has 
appeared among the ends of the fibers of the central spindle. 
In fig. 5 the cell plate elements have fused into a cell plate, the 
fibers have shortened still further, and the trophoplasm appears. 
Eee Pigs is especially important. Here the fibers have 
become very short and the ends furthest away from the cell 
plates are no longer surrounded by the granular trophoplasm. 
These ends appear to be sharp pointed, while the portion of each 
fiber that is in connection with the cell plate is relatively thick. 
i stage the trophoplasm becomes distributed more 
oo the region originally occupied by the central spindle. 
se it oy appears in irregular rows of granules ( fig. 7)» 
ma % atter figure very small portions of the spindle fibers 
Pe oa They show the typical pointed structure above 
as and are distinct from the rows of trophoplasm. 
the ai ae all of ane processes involved in the formar of 
Strong] ck. the spindle fibers and the cell plate itself stain 
the Re the “iolet of the triple stain. I have not observed 
described transition from the violet to the orange color 
when th y Strasburger for the spindle fibers at the time 
€ cell plate is formed. Not only do the spindle fibers. 
and 
the cell plate stain violet, but the plasma membrane of the: 
*Zelihinte. 
