Cytology and Movements of the Cyanophycee. 241 
Such conflicting evidence is the result, it would seem, of 
two factors: first, the want of any uniform meaning for the 
word “nucleus” among the different observers; and second, 
the failure to recognize that the nucleus and other cell con- 
tents may give different reactions with the same reagent at 
different times. This latter fact has been abundantly shown 
by the nuclei of higher organisms during division and other 
life phases, where varying concentrations and modifications 
of the nucleic acid (52) may occur. Why the same variabil- 
ity should, among the nuclei of the lower forms, be taken 
as indicating a different morphological structure is hard to 
conceive. The fact that protoplasm itself is a mixture of 
various complex bodies, which through metabolism and 
growth are continually changing, would leave no valid 
reason for considering that variations in the cell contents, 
even as profound as those of the “central body” of the 
Cyanophycean cell should not exist. 
The earlier writings on the cytology of the Cyanophycee 
were by Schmitz in 1879. He did his work upon Gloeo- 
capsa polydermatica, Oscillaria princeps and Anabaena flos- 
aquae. In his earlier work (67), after many attempts, he 
discovered a homogeneous central body which he consid- 
ered to be a cell nucleus, though it did not seem to appear 
in every cell of all preparations. Hematoxylin showed this 
nucleus of Oscillaria princeps to be spherical and excentrically 
placed. He also found the cells to be more or less com- 
pletely filled with large round granules of unknown com- 
position, which he called “schleimkugeln.’’ Though he used 
hzmatoxylin to stain his preparations, he was able to make 
out the structure equally as well without its use. He there- 
fore discarded the stain and drew his conclusions from the 
fresh, unaltered material. 
The following year Schmitz (68) again published on the 
cytology of the Cyanophycez. Here he retracted his views 
of the former year, declaring that these plants were non- 
nucleolated and non-nucleated. The central body, which 
