IRON COMPOUNDS IN ANIMAL AND VEGETABLE CELLS. 263 
regard all the granules as nuclei, the next investigator of this 
subject is Hieronymus,! who found in these cells a thin hya- 
line membrane externally, a chromatophore, and a central 
body consisting of a single much-wound fibril, comprehending 
in its turns all the granules in the cell. The granules he looks 
upon as crystals belonging to the regular system, and composed 
of a substance ‘ cyanophycin,”’ which, though not identical 
with nuclein in its reactions, he regards as related to the 
chromatin and pyrenin of highly specialised vegetable cells. 
The central body is, in his opinion, an “ open nucleus.” 
According to Palla? the cells in the Cyanophycez consist of 
a chromatophore with a vesiculated structure, of a central 
homogeneous body, and of granules of different composition 
always outside the latter. The central body is affected, like a 
nucleus, by staining reagents. In preparations fixed with 
corrosive sublimate and stained with Bohmer’s hematoxylin 
the granules adjacent to, or in contact with, the central body 
are stained reddish-violet, while those scattered in the chroma- 
tophore are coloured blue. He finds that those which thus 
become blue dissolve in dilute solutions of hydrochloric: acid 
(0°3 per cent.) and do not stain intra vitam when treated 
with solutions of methylene blue. The substance constituting 
these, and which he calls ‘‘ cyanophycin,” he regards as the 
first assimilation product of the activity of the chromatophore. 
Those which stain reddish-violet with hematoxylin are com- 
posed of a viscid substance, are not soluble in dilute acids, and 
in the living cell manifest a strong affinity for methylene blue, 
To such structures he has applied the name ‘‘ mucous sphe- 
rules,” first given them by Schmitz. They correspond with 
the granules which, in Bitschli’s preparations, stained red 
with hematoxylin, but, in opposition to the views of that 
observer, Palla regards it as extremely doubtful if they contain 
any compound comparable to chromatin. 
1 « Beitrage zur Morphologie und Biologie der Algen,” Cohn’s ‘ Beitrage 
zur Biologie der Pflanzen,’ vol. v, 1893, p. 461. 
2 “Beitrag zur Kenntniss des Baues des Cyanophyceen-Protoplasts,”’ 
Pringsheim’s ‘ Jahrbiicher fiir wiss. Bot.,’ 18938, vol, xxv, p. 511. 
