ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 423 
macese, Silicoflagellata, and Cilioflagellata. After some general remarks, 
the species are described in detail. The Diatoms belong chiefly to the 
genera Ghsetoceros and Coscinodiscus. The modes of reproduction of 
Ghsetoceros are described in detail, and the species are arranged in two 
subgenera, Plneoceros, with thick, often spinous setae, hollow, and filled 
with protoplasm and chromatophores ; and Hyalochaete, with slender 
colourless setae. There are a number of new species. The Silicoflagel- 
latum found is Bistephanus speculum ; and the Cilioflagellata are Cera - 
Hum tripos and C . fusus. 
Structure of Cyanophycese and Schizomycetes.* — After a detailed 
account of the researches and views of other observers on the structure 
of these organisms, Herr A. Fischer expounds his own views, which are 
in strong opposition on several points to those of Biitschli. 
In the first place he contends that staining reactions are dependent 
on the physical rather than the chemical structure of the object ; that, in 
particular, there is no true nuclear pigment ; and that the staining pro- 
perties offer no certain indication of the place of the object stained in 
any special group of proteid-substances, or of the morphological value 
of a cell-element. 
The Cyanophycese possess a true parietal chromatophore, which is 
usually cylindrical ; in it lies the so-called central body. This cannot 
be regarded as the phylogenetic ancestor of the nucleus of higher 
plants ; it possesses no true chromatin ; its granulations are simply 
collections of reserve-substances. 
In the sulphur-bacterium Chromatium the pigment is not collected 
into a peripheral layer, but colours the cell-contents uniformly ; there is 
no differentiation into a cortical and central portion. Neither in Chro- 
matium nor in Beggiatoa is there any structure which can be regarded 
as a nucleus. The figment of a central nucleus is the result of plasmo- 
lysis. The bacterium-cell consists of a parietal layer of protoplasm, 
and an inner cell-sap-cavity which may be traversed by septa of proto- 
plasm. 
The author regards the Bacteria as more nearly allied to the Flagel- 
lata than to the Cyanophycese. 
New Genera of Cyanophycese. — Under the name Loefgrenia anomala 
g. et sp. n., M. M. Gomont j* describes what he regards as probably the 
type of a new family of Nostocacese. The following is the diagnosis of 
the genus : — Planta myxophycea, filamentosa ; trichomata evaginata, basi 
affixa, pilifera, in parte inferiori passim ramosa, ramificatione vera; 
heterocystse nullse ; homogonia et sporae usque adhuc ignota. 
Among a large number of new species from tropical Africa, Messrs. 
W. and G. S. West J find the following new genera : — 
Camptothrix. Plantm minutse, filamentosse et epiphytic® ; fila brevis- 
sima, haud ramosa, e serie singula cellularum irregularium formata, 
supra algas majores aquaticas repentia, irregulariter flexuosa et sub- 
moniliformia, vaginata ; vagina delicata, arcta et hyalina ; cellulse sub- 
* ‘Unters lib. d. Ban d. Cyanophyceen u. Bakterien,’ Jena, 1897, 136 pp. and 
3 pis. See Bot. Centralbl., Ixxi. (1897) p. 62. Cf. this Journal, ante, p. 235. 
f Wittrock, Nordstedt, and Lagerkeim; Algse aqu® dulcis exsiccatce, fasc. 26-9, 
Stockholm, 1896. 
X Journ. of Bot., xxxv. (1897) pp. 261-72, 297-301 (l pi. and 2 figs.). 
