1898-99. ] ON THE CYTOLOGY OF NON-NUCLEATED ORGANISMS. 441 
THE CYANOPHYCE. 
].—LITERATURE. 
The first to examine carefully the structure of the Cyanophycee was 
Schmitz,’ who found in the cells of Gleocapsa polydermatica a homo- 
geneous central portion which stained with haematoxylin and represented, 
as he thought, the nucleus of the cell. He found also that there were in 
the cell substance a number of spherules of unknown composition, to 
which he applied the term “Schleimkugeln.” In the cells of Osczllaria 
princeps, after being stained with haematoxylin, he observed a dark, 
spherical, somewhat excentrically placed body which he regarded asa 
nucleus, but he was unable to demonstrate its presence in all preparations 
of this form. 
Further observations,? however, led Schmitz to regard the cells of 
Cyanophycee as non-nucleated and the supposed nuclei of Glgocapsa as 
simply very large chromatin granujes which react with haematoxylin like 
the chromatin granules of the nuclei of higher organisms. He dis- 
tinguished in Oscéllaria princeps a peripheral, finely punctated zone in 
each cell which stained with hematoxylin less deeply than the central 
portion. 
In alater work ue denies the existence of a chromatophore and claims 
that the functions performed in the special parts of highly differentiated 
cells, are in the Cyanophycee the property of the cell protoplasm 
generally. 
Tangl* also was unable to determine the presence of a nucleus, but 
he found a chromatophore in Plaxonema Oscillans. According to 
Wille,’ however, a nucleus exists in Tolypothrix lanata. After being 
stained with a dilute or a concentrated hematoxylin solution, preferably 
the latter, the nucleus appeared faint blue, the nucleolus, on the other 
hand, intense blue, while the remaining cell contents were scarcely 
stained. In the dividing eell he observed two nuclei, each with a 
1 ‘Untersuchungen tiber den Zellkerne der Thallophyten,” Sitzungsb, der Niederh. Gesell. fiir Natur— 
und Heilkunde zu Bonn. Sitz. vom August 4, 1879, p. 355+ 
2 ‘Untersuchungen tiber den Strukter der Protoplasma und der Zellkerne der Pflanzenzellen," Ibid, 
Sitz, am Juli 12, 1880, p. 159. 
3 ‘* Die Chromatophoren der Algen,” Bonn, 1882, quoted by Deinega. 
4 ‘* Zur Morphologie der Cyanophyceen,” Wien, 1883. 
5 ‘‘Ueber die Zellkerne und die Poren der Wande bei den Phycochromaceen,” Berichte d, deutsch, 
bot. Gesell., Vol. I, 1883, p. 243. 
