ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 471 



budding off of conidia in large numbers. The conidia are oval, 

 measuring 1 /x by 1-75 /*. After rupture of the spore membrane, the 

 freed vegetable-cell exhibits a faint motility. 



The author considers that this organism, from a phylogenetic point 

 of view, serves to connect the iron bacteria, Leptothrix, Galionella, 

 Cladothrix and Crenothrix, with the genus Spiromonas. 



Bacillus nitrator, B. azotofluorescens, and B, hiltneri.* — H. 



Kaserer describes some new autotrophic nitrogen bacteria. One of 



these, B. nitrator^ converts ammonia directly into nitrates. It is a long, 



^ moderately thick bacillus, which forms dense white colonies, and does 



not liquefy gelatin. 



B. azotofluorescens decomposes ammonium formate into nitrogen and 

 formic acid, and then utilises the formic acid ; in the absence of 

 combined nitrogen it produces ammonium carbonate from formic acid 

 and atmospheric nitrogen. 



B. hiltneri. decomposes cyanides with production of nitrogen and 

 carbon-dioxide, and also fixes free nitrogen in presence of sugar. 



* Zeitschr. Landw. Versuch. Oesterr., pp. 37-4. See also Journ. Chem. Soc.,. 

 xci.-xcii. (1907) abst. 2, p. 381. 



