16 
Olive, Mitotic division of tlie miclei of tlie Cyanopliyceae. 
be confined to tlie peripheral denser portion, and only in tlie 
central colorless (or at times slightly greenish) region will be 
observed tlie granules, now distinctly colorless, wliicb we liad 
previously remarked in side view. The color is in this instanc-e 
not caused by niinnte green granules, bnt it appears rather to 
be due to a uniformly diffused substance, confined to tlie peri- 
pheral, sonietimes distinctly fibrous, region which Fischer calls 
tlie chroniatopliore. Such a chroinatophore probably tinds its 
parallel in many of the lower algae, in TJlothrix , for example, in 
Hydrodictyon , and others. 
The granulation in Gloeocaysa is clearly visible, both in the 
living condition as Avell as in tlie cell treated with Chloroform 
Avater. Fig. 36 represents a cell so treated, with much of the 
pliycocyanin still confined in the space between the shrunken 
cell and tlie thic-k, gelatinous nienibrane. In this condition, it 
is impossible to say Avhether tlie granules which Ave can see so 
clearly are green or not. But when tlie Chloroform water is 
alloAA^ed to act for several days, sometimes the wall of the dead 
cell is broken doAvn (fig. 35), leaving imbedded in the firm ge¬ 
latinous nienibrane nothing but tlie multitude of colorless gra- 
nules. These granules, which Schmitz called slime globules, 
are probably, therefore, merely granules of reserve foocl matter, 
although the writer is not yet prepared to say that they are 
cyanophycin. 
The central hody. 
Schmitz Avas the first, in 1879, to call the central body in 
tlie cell of Gloeocapsa a nucleus. The very next year, however, 
(80) he canie to the conclusion, after further study, that the 
nahrate granules of this central portion Avere microsomes and 
that they did not represent a nucleus. This opinion he repeated 
three years later (83), after studying many Cyanopliyceae, and 
he made the general statement that these plants possessed cells 
Avithout nuclei. Zacharias (87) after his first studies on Toiy- 
pothrix and Oscillatoria , also held tlie opinion that tlie central 
body contains chromatin and that it represents a nucleus, but, 
later (90), he saw reasons to modify his vieivs and concluded 
that, although the body in question contains chromatin, it is 
probably not a nucleus. To tliis opinion, Zacharias eAndently 
still clings. 
Mac all u m (99) also holds a similar vieAV, that, although he 
lias demonstrated that chromatin is present in tlie cells of the 
Cyanopliyceae and tlie Bacteria , they are neA r ertlieless non-nu- 
cleated organisms. On tlie contrary, LaAvson (03) contencls that 
the chromatin granules represent tlie nucleus, „since e\^ery high ly 
organizecl nucleus passes through a stage in its development 
when it consists of nothing but chromatin.“ 
Others avIio believe that the central body is not a nucleus 
are Marx (92), avIio, indeed, could see a central body „nur äußerst 
selten“, Palla (93), Cliodat (94), Stockmayer (94), Fischer 
