242 Phillips on a Comparative Study of the 
he formerly considered to represent the nucleus, he now 
interpreted as very large microsomes which reacted like the 
nuclei of the higher plants. The peripheral protoplasm he 
found crowded with larger or smaller granules which 
stained deeply with hzmatoxylin like chromatin granules 
in other plants. This peripheral layer is what Schmitz 
busied himself with mostly in his second and third (69) 
papers, in the last of which he concluded that he was unable 
to find any specially formed nucleus or chromatophore in 
either the Cyanophycez or the Bacteria. 
It is interesting to note that in his earlier work, Schmitz 
saw a homogeneous central portion which he called a 
nucleus. There was also a granular periphery to the cell 
which resembled a chromatophore. In his later works he 
still found a central body, but because it broke up into 
“microsomes,” he no longer interpreted it as a nucleus, but as 
granules which were composed of nuclear constituents. His 
later works were given over to the study of the chroma- 
tophores more particularly. These he also failed to find, 
but attributed the function usually performed by such organs 
in the higher plant cells to the general protoplasm of the 
Cyanophycee. 
Wille (85) worked principally upon Tolypothrix lanata, 
which he stained with hzematoxylin, preferably concen- 
trated. He could make out a dark blue nucleolus, which 
in nature is relatively quite large and colorless, and a pale 
blue nucleus in an unstained cytoplasm. The nucleus 
could also be seen in the granular cells when treated with 
dilute acetic acid. He also succeeded in demonstrating an 
intercellular continuity of the protoplasm in Stigonema com- 
pactum, Ag. At the time of cell division, which he was 
able to observe clearly, he found that each cell nucleus 
divided into two nuclei, each having one or two nucleoli. 
Thereafter the dividing cell wall was laid down. He did 
not claim a nucleus for all of the Cyanophycez, but regarded 
it as always present in the higher forms. 
