ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
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results, according to him, from a vacuolisation of the central region, and 
does not differ in any essential respect from the rest of the protoplasm ; 
it is often as strongly coloured as the peripheral protoplasm. Muci- 
lages, soluble starches, and cyanophycin may appear in all parts of the 
protoplasts, though they are liable to accumulate especially in the 
central portion. This first division-wall of Chroococcus turgidus is 
protoplasmic and coloured. 
Prof. R. Chodat and Mdme. Balicka * * * § have continued their investi- 
gations of the cell-contents of Tolypothrix , Bivularia, Oscillatoria, and 
Stigonemci. In no case were there found any granulations incapable of 
staining, with the exception of vacuoles. In the first-named three genera 
these granulations always occupy the central region, and the peripheral 
zone to a less degree ; in Stigonema they are equally distributed over 
the whole cell. The cell-wall cannot be distinctly differentiated from 
its contents. 
Protoplasts of Cyanophyceae.f — Herr G. Nadson adopts Butschli’s 
view of the honeycomb structure of the protoplast of the Cyanophycese, 
not only of the green peripheral layer, but also of the central body ; the 
meshes are filled with phycochrome-chlorophyll. The central body is 
not sharply differentiated. Among the cell-contents of the Cyanophycese 
are three kinds of granular structure : — (1) chromatin-grains, corre- 
sponding to the red granules of Biitschli, the Schleimkugeln of Palla, and 
partially to those of Schmitz, and to a portion of the cyanophycin-grains 
of Hieronymus; (2) protoplasmic microsomes; (3) reserve-granules, 
which occur only in the peripheral layer, corresponding to the cyano- 
phycin-grains of Borzi and Palla, and to a portion of those of Hieronymus ; 
they perform the function of the starch in the higher plants. In cell- 
division, the whole of the protoplasm becomes constricted into two halves. 
The central body of the Cyanophycese corresponds in many respects to 
the nucleus of higher plants. 
The protoplasm of the larger bacteria agrees in structure with that 
of the Cyanophycese ; in most of the smaller ones there is, on the con- 
trary, no differentiation into central body and peripheral protoplasm. 
For the protoplast of the Cyanophycese and Schizomycetes the author 
proposes the term archiplast. 
Calothrix producing Spores.f — M. M. Gomont has found, in a marsh 
in France, growing attached to a Cladophora , a Calothrix which he names 
C. stagnalis sp. n. It is characterised by the production of spores, 
always at the base of the trichome, not in chains, but singly or less often 
in pairs, one superposed on the other. The sporiferous branches present 
the appearance of a Gloeotrichia. 
Stigonema.§ — Dr. G. Hieronymus discusses the distinctions and the 
synonymy of the species described by authors of this genus of Sirosipho- 
nese, especially in reference to the species S. ocellatum, panniforme , 
tomentosim, and minutum . A new species, S. Glaziovii , is established. 
* Arch. Sci. Phys. et Nat., xxxiii. (1895) pp. 206-8. 
f Scripta Botanica, iv. (1895) 76 pp. and 2 pis. See Hedwigia, xxxiv. (1895) 
Rep., p. 46. Cf. this Journal, ante, p. 213. 
X Journ. de Bot. (Morot), ix. (1895) pp. 197-202 (2 figs.). 
§ Hedwigia, xxxiv. (1895) pp. 154-72. 
