FERMENTATION — -BACTERIOLOGY. 9l5 



and in one ease very pure. The decrease of bacterial content reaches 

 its maxinuini between 24: and 48 hours, after which there is a marlied 

 increase. This has an economic bearing, showing that where this 

 method of purification is used on a large scale it is necessary to treat 

 small quantities of water in separate reservoirs, to be used within the 

 following day. 



Fermentation of galactose, F. Dienert {A717}. Tiist. Pasteur^ I4. 

 {IDOO), Xo. o,j)jj. 130-lSO). — Researches on the fermentation of galac- 

 tose and the accustoming of yeasts to this sugar are summarized by the 

 author. The process by which the yeasts become accustomed to and 

 capable of fermenting galactose is called by the author acclimatization. 

 Galactose is said to be a fermentable sugar when a yeast has become 

 accustomed to it. The duration of acclimatization varies with the 

 different species of yeasts, being quite favored with the lactose ferments. 

 Glucose is fermented 1.6 times more quickly than galactose by accli- 

 matized yeasts. The required characteristic of fermentation is lost if 

 sugar other than glucose, lactose, or melibiose be offered to the yeast. 



The morphological characters of yeasts are in no way altered by accli- 

 matization. Certain substances, such as boric acid, toluene, etc., may 

 prevent acclimatization without preventing fermentation of glucose. 

 When a yeast has lost its zymase by cultivation in a medium rich in 

 peptone, it can not be made to ferment galactose until it has been 

 revived with glucose. But, if previously acclimatized to galactose, it 

 can be revived with that substance. During the process of acclimatiza- 

 tion only one zymase undergoes a change of constitution, and this 

 change is attended with profound alteration of the protoplasm. The 

 phenomena of acclimatization is a profound modification of the con- 

 dition of the cell induced by a carboh3'drate closely allied to glucose. 

 A comparison is made between yeast ferments and antitoxins, which 

 latter not only accustom leucocytes to toxins but also act as antidotes. 



The essentials of practical bacteriology: An elementary laboratory book 

 for students and practitioners, II. J. Curtis and M. D. Lond {London: Longmans, 

 Green. A- Co., lUOO). 



Tbe elements of general bacteriology, N. Gamaleia (Elemente der allgemeinen 

 Bdder'iologie. Berlin, 1900, }>p.:.'47). 



On the structure and development of bacteria, F. Ve.idovsky {Centhl.Bukt. u. 

 Par., 2. Aht., G {1000), Xn. IS, pp. 577-589, pi. 1). 



A critical study of the processes of denitrification, O. Lemmermanx {Inaug. 

 Dins., Jena, 1900, pp. 91). 



The physiology and morphology of alcoholic ferments, E. C. Hansen {f'ompt. 

 Rend. Traraux Lab. Carlsberg, 5 {1900), No. 1, pp. 1-38, figs. 5). — Studies are given on 

 the varieties of Saccharomyces, in which the form of cells, formation of spores, bud- 

 ding, chemical action, growth in various nutrient media, and conditions of the various 

 transformations undergone by the plant are described. 



The formation of enzyms by alcoholic ferments, a specific characteristic, 

 A. Klocker {Compt. Bend. Travaux Lab. Carlsberg, 6 {1900), No. 1, pp. 58-63).— 

 Studies are reported on a number of species of Saccharomyces, from which the author 

 concludes that the formation of enzyms is quite constant among the different species. 



