282 Phillips on a Comparative Study of the 
pores on the sides where cilia pass through. The same is 
true of Cylindrospermum and such other forms as possess 
these organs. They are best seen after corrosion with iodine 
and sulphuric acid (Figs. 27 and 63) when the wall becomes 
swollen and the pores become more evident. In the cells 
figured, the sulphuric acid has so plasmolized the protoplast 
as to cause it to withdraw the protoplasmic processes from 
the pores, leaving them empty and distinct, while the proto- 
plasmic fingers which passed through them are shown pro- 
jecting from the protoplast. In cross sections made with the 
microtome, these pores are quite evident, especially if the 
organism has been cultivated for a few days in a dilute 
solution of palladious chloride. 
The Central Body. 
The protoplast of the Cyanophycean cell is definitely 
divided into two portions, the central body and the outer 
protoplasmic zone. This distinction can usually be deter- 
mined in the living cell. The central body in living material 
is generally quite colorless and fiiled with large grains or 
“slime balls’ as they have been termed by some investi- 
gators. These balls may be so large as to give the appear- 
ance of a fragmented central body (Fig. 37). From their 
position and reaction, these are evidently what Butschli (9) 
termed the “red granules,’ on account of their staining 
a reddish blue with Delafield’s hematoxylin. Buttschli con- 
sidered them to be composed of chromatin. Palla and Stock- 
meyer could not find them within the central body, but upon 
the outside of it, the reactions were such, however, as to lead 
them to conclude that they were composed of chromatin. 
When colored by the ordinary nuclear staining methods and 
stains, they are shown to have a periphery composed of a sub- 
stance reacting exactly like chromatin, while the central part 
does not seem to take up the stain at all or very slightly. The 
central body therefore appears as if composed of a number 
