1899 ] SPORE-MOTHER-CELL OF ANTHOCEROS 93 
The phenomenon of division is one of simple constriction in the 
middle region and final separation of the halves as the furrow 
deepens around the chloroplast. It is very plain that the line of 
fission is determined by the furrow and not from the interior of 
the chloroplast. Therefore if any particular region of the 
protoplasm is actively concerned in this process one would 
naturally first seek the agent in the peculiar film bounding the 
chloroplast. However there is little in the structure of this 
region to indicate such important activities. 
After the first division of the chloroplast the two portions 
usually separate and pass to opposite ends of the elongated spore- 
mother-cell ( fig. 6). Each has a structure quite similar to the 
parent chloroplast except that the starch grains become even 
more numerous and prominent and the fine strands and films of 
protoplasm separating the starch grains are less clearly defined. 
oon after this first division of the chloroplast there takes place 
that peculiar condition of the nucleus termed synapsis, but this 
phenomenon had best be considered in a later portion of the 
Paper that deals with nuclear activities. There is a well defined 
period when the spore-mother-cell has only two chloroplasts, and 
no longitudinal section of the sporogonium will fail to exhibit a 
fegion in which all of the cells are in this condition. As a spore- 
mother-cell grows older, and increases still further in size, indica- 
tions of the approaching second division of the chloroplast 
become manifest. 
The second division of the chloroplast repeats exactly the 
Phenomenon of the first division. As a rule both structures 
“oncerned are active at the same time, but one may be in a more 
Pe ae of fission than the other. The proportions of the 
OE eae at this time are more nearly equal (As: 7) 
portion tis it aia condition, z. ¢., the cell is| broader in as 
tributed ou Sati As a result the four chioroprast are dis- 
ive the centrally placed nucleus in such a pane 
divisicnaot a the greater part of one of the four tetrahedra 
Fation: of ty 1€ spore-mother-cell that are present after she sepa- 
€ cell contents to form the spores. Sometimes the 
