ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 1007 



Protophyta. 



Micro-organisms.* — In bis work ' Die Mikroorganismen,' Prof. M. C. 

 Fluegge adopts the classification of cle Bary and Frank, and passes in review 

 all the pathogenic species of Hypodermii, Peronosporeae, Pyrenomycetes, 

 and Mucorini, as well as those of Schizomycetes. In the case of Aspergillus 

 fumigatus and glaucus, he states that the spores, if injected in sufficient 

 quantities into the veins of a rabbit or guinea-pig, rapidly cause death. If 

 rabbits, pigeons, or other small birds are placed in an atmosphere holding 

 Aspergillus spores in suspension, the bronchials and kidneys become rapidly 

 filled with the mycelial filaments ; and the same is the case with Erysiplie 

 and Oidium. With Grawitz, the author identifies Oidium lactis, Achorion 

 Schoenleinii, Trichophyton tonsurans, and Microsporon furfur as forms of the 

 same species. 



The Schizomycetes are classified by Prof. Fluegge under four principal 

 groups, viz. : — (1) Micrococcus (including Staphylococcus, Streptococcus, 

 Diplococcus, Ascococcus, and Sarcina) ; (2) Bacillus (including Bacterium) ; 

 (3) Spirillum ; and (4) a group allied to Nostocaceae, comprising Leptothrix, 

 Crenothrix, and Beggiatoa. Each of the first two groups is again divided 

 into jjathogenic and saprophytic forms. The phenomena connected with 

 gelatin culture are dwelt on in detail with each species. The author 

 inclines to the view of Koch and Cohn with regard to the genetic distinction 

 of the various forms, rather than to that of Zopf. 



Rose-tinted Growth on Fresh Water-t — Herr J. B. Schnetzler, confirm- 

 ing the observation of Dr. Harz, describes a red substance floating on the 

 surface of the Lac de Bret (Switzerland) due to the coccus-form of 

 Beggiatoa roseo-persicina. In the same lake he found the dead bodies of 

 flies attacked by the slender colourless leptothrix-filaments of the Beggiatoa, 

 accompanied by its blackish zoogloea-form. From this latter the leptothrix 

 was found to spring directly without any intermediate bacillus-form. 



Sulphur-bacteria.J — Herr S. Winogradsky proposes this term for that 

 group of non-chlorophyllous protophytes distinguished physiologically by 

 the property of reducing sulphur out of its solutions. In this group he 

 includes Beggiatoa alba aud its varieties, Monas OJcenii, M. vinosa, Glathro- 

 cystis roseo-persicina, Sarcina sulphurata n. sp. (possibly identical with 

 S. rosea), Ophidiomonas sanguinea, and probably others. His observations 

 were made chiefly on Beggiatoa alba obtained from natural sulphur-springs. 



The author finds that the presence of sulphates, especially calcium 

 sulphate, in the water, is not only advantageous, but is absolutely essential 

 for the healthy growth of Beggiatoa ; but that, although, under such circum- 

 stances, reduction of the sulphates and formation of sulphuretted hydrogen 

 takes place, the Beggiatoa takes no part in this reduction ; the source of 

 the sulphur in its structure is invariably the oxidation of sulphuretted 

 hydrogen already present in the water. He confirms Hoppe-Seyler's state- 

 ment that it cannot maintain its existence without access of free air. It 

 appears, however, to require much less oxygen than most organisms ; and 

 where the supply of air is abundant it rapidly perishes. An excess of 

 sulphuretted hydrogen also destroys it. By culture-experiments the author 



* Fluegge, M. C, 'Die Mikroorganismen,' 692 pp. and 144 figs., Leipzig, 1888. 

 See Bull. Soc. Bot. France, xsxiv. (1887) Rev. Bibl., p. 77. 



t Bot. Centralbl., xxxi. (1887) p. 219. Cf. this Journal, ante, p. 787. 



X Bot. Ztg., xlv. (1887) pp. 489-507, 513-23, 529-39, 545-59, 569-76, 589-94, 

 606-10 (3 figs.). 



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