ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 713' 



Bacillus variabilis lymphae vaccinalis.* — Dr. K. Nakanisbi has 

 found from further investigation, that B. variabilis lymphae vaccinalis 

 is a constant habitant of the normal skin of men and animals, and there- 

 fore has no astrological relation to vaccinia or variola. The cultures 

 were therefore contaminated with the real pock-microbes, which at pre- 

 sent remain unknown- 

 Mechanism of Agglutination.! — Mr. E. Greig Smith, after alluding 

 to the views of previous observers regarding the mechanism of aggluti- 

 nation, states that it appears to him that agglutination is caused by the 

 formation of a delicate precipitate on the outer surface of the bacteria 

 and in the fluid in which the bacteria are suspended. This precipitate 

 is flocculated or coagulated by the saline constituents of the medium and 

 of the serum. Since the precipitate is invisible to ordinary micro- 

 scopical observation and the bacteria are visible, an apparent agglutina- 

 tion of the latter only is seen to take place by tbe action of active sera. 



Fischer's Structure and Functions of Bacteria.J — Prof. A. Fischer's 

 Lectures on Bacteria have been translated into English by Mr. A. Cop- 

 pen Jones, who has performed his task in a most admirable manner. 

 The Lectures on Bacteria were intended to serve as an introduction to 

 the subject and to form a concise compendium of the vast literature of 

 the science. The intention of the author has been fully attained ; the 

 outlines are drawn with a firm and masterly hand ; and though the text 

 amounts to but 168 pages, nothing necessary to a full comprehension of 

 tbe subject has been omitted. Besides what is generally accepted, the 

 work includes some novelties, such as the author's own classification 

 of bacteria, and also a suggestion that modes of life might serve as a 

 basis for classification. According to this view, Bacteria might be 

 divided into three biological groups, — the prototrophic, metatrophic, 

 and paratrophic. The prototrophic species are those which require little 

 or no organic compounds for their nutrition, e.g. nitrifying bacteria, 

 bacteria of rod-nodules, sulphur and iron bacteria. The metatrophic 

 include the zymogenic, saprogenic, and saprophile bacteria, and cannot 

 live unless they have organic substances (nitrogenous and carbonaceous) 

 at their disposal. The paratrophic exist only in the tissues and vessels 

 of living organisms and are true (essential) parasites. The scope of the 

 work may be more nearly appreciated from a consideration of the chief 

 topics discussed. The Morphology and Taxonomy are first dealt with, 

 after which the author passes on to the Distribution and Origin, the 

 Physiology of the Nutrition and Eespiration of Bacteria. Then come the 

 Influence of physical agents, and the Action of chemicals. These are 

 followed by Bacteria and the circulation of nitrogen in nature, and the 

 Circulation of carbon dioxide in nature; the work concluding with three 

 chapters on Bacteria in relation to disease. Appended are some useful 

 and explanatory notes. 



Now, F. G. — Laboratory Work in Bacteriology. 



2nd edition, Ann Arbor, Michigan, 1900, 563 pp. 



Symes, J. O. — Bacteriology of Every-day Practice. London, 1900, 8 vo. 



* Centralbl. Bakt. u. Par., l ,e Abt., xxviii. (1900), pp. 304-5. Cf. this Journal, 

 ante, p. 506. 



t Proc. Linn. Soc. N. S. Wales, 1900, pp. 75-83. Cf. this Journal, ante, p. 501. 



X Oxford, Clarendon Press, 1900, 168 pp. text, 29 figs. Cf. this Journal, 1898 

 p. 231. 



