ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
563 
six to ten swarmspores. The swarmspores of Codiolum Petrocelidis have 
four cilia. 
Antherozoids of Dictyota and Taonia.* * * § — Mr. J. LI. Williams has 
detected motility in the antherozoids or pollinoids of Dictyota and 
Taonia, hitherto supposed to be immotile. On escaping from the antherid, 
the antherozoids were seen to swarm, and to display as great activity as 
those of Fucus. The cilia were clearly displayed on staining ; but it is 
stated that there are striking differences between the phenomena and 
those of the Fucaceae. 
Arrested Condition of Zygnema.|— Herr W. Schmidle describes a 
peculiar condition of a Zygnema from Australia, in which the protoplasts 
of the cells have undergone contraction into a spherical form, giving a 
torulose appearance to the filament. It appears to mark a transition 
between Zygnema and Zygogonium, to which latter genus it should pro- 
bably be referred. 
Fungi. 
Influence of Nutrient Media on the Development of Fungi. — M. 
J. Ray J has grown examples of the lower Fungi, chiefly Sterigmatocystis 
alba, in a variety of nutrient media, and finds the one character which 
remains constant to be the size of the spores. Almost all other charac- 
ters which are relied on as specific are liable to vary, while those which 
are regarded as generic are for the most part constant. The size of the 
cells of the filaments which compose the thallus is especially variable. 
When cultivated in liquids in motion, the cells are liable to assume a 
spherical form, or the thallus itself becomes rounded. In nature the 
vegetative elements springing from spores of the same origin may vary 
greatly, according to the conditions of germination and development. 
Herr A. Schmidt § gives full details of the effects of various nutrient 
fluids of different degrees of concentration on the development of the 
conids, gemmae, and ascus-fructification of Sterigmatocystis nidulans. 
Herr W. Schostakowitsch || has investigated the changes produced in 
Mucor proliferus ^ by external conditions. It varies exceedingly according 
to the temperature and the nature of the nutrient fluid. It may vary 
in height between 0’5 mm. and 7 cm. Swellings may appear below the 
sporanges, as in Pilobolus. The wall of the sporange may lose its deli- 
quescent property. The spores are subject to extraordinary variation in 
size, viz. between 2 and 67 /x ; they may become curved or lobed, hour- 
glass-shaped or cylindrical, and may germinate within the sporange. 
As the result of experiments made on some of the lower Fungi, 
Aspergillus niger , Penicillium glaucum, and Botrytis cinerea, Mr. H. M. 
Richards ** finds that many nutrient substances, both organic and inor- 
* Journ. of Bot., xxxv. (1897) pp. 361-2. 
f Flora, lxxxiv. (1897) Erganzbd., pp. 167-70 (11 figs.). 
i Rev. Ge'n. de Bot. (Bonnier), ix. (1897) pp. 193-212, 245-59, 282-304 (6 pis. 
and 4 figs ); Comptes Rendus, cxx. (1897) pp. 193-4. 
§ • Ueb. d. Bedingungen d. Conidien-, Gemmen-, u. Schlauehfrucht-Production 
bei Sterigmatocystis nidulans ,’ Halle, 1897 (1 pi.). See Bot. Centralbl. lxxi. (1897) 
p. 98. || Flora, lxxxiv. (1897) Erganzbd., pp. 88-96 (1 pi.). 
«|[ Cf. this Journal, ante , p. 149. 
** Jahrb. f. wiss. Bot. (Pfeffer u. Strasburger), xxx. (1897) pp. 665-88. 
