and Laboratory Methods. 2585 

 ^ 



CURRENT BACTERIOLOGICAL LITERATURE. 



H. W. CONN, Wesleyan University. 



Separates of Papers and Books on Bacteriology should be Sent for Review to H. W. Conn, 

 Wesleyan University, Middletown, Conn. 



Lafar, Dr. Franz. Technical Mycology. Vol. All acquainted with the first volume of 



II pt I, pp. 189. Figures 67. Published by Lafar's Mvcologv will welcome this first 

 J. B. Lippincott & Co., Philadelphia. ^ ^^ 



part of volume II. Although the part 



now issued does not complete the second volume, the English publishers have 

 had so many calls for the companion volume to the one already published that 

 they have issued the first part separately instead of waiting for the completion of 

 the work by the author. The rest will be translated as soon as possible. The 

 new volume just issued deals with Eumycetic fermentation. Three chapters are 

 devoted to the general morphology of the moulds and their allies, their chemical 

 composition and the eyzymes produced by them. The rest of the work is con- 

 fined to the study of the Mucors and yeasts. As indicated in the title the 

 subjects especially dwelt upon are those which concern the practical relations of 

 Mucors and yeasts to industrial operations. Nevertheless, enough of general 

 morphology and chemistry is given to make the work useful to the scientist as 

 well as to the technical student of fermentative industries. The use of yeasts 

 in fermentation is of course well known, but most readers will be somewhat 

 surprised to learn that the Mucor family is also of considerable practical use in 

 various fermentative industries. Lafar has an exceptionally clear style of 

 writing and shows an ability of selecting for description and explanation exactly 

 the questions that are likely to puzzle the student. The work is a very valuable 

 one and should find its way to the bookshelves of all bacteriologists, h. w. c. 



Holliger. Bakteriologische Untersuchungen This author makes a very interesting 

 liber Mehlteiggarung. Cent. f. Bact. u. series of studies upon the fermentation 

 Par. II, 9 : 305, 1902. .... 



of bread dough for bread raising, by 



the use of sour dough (leaven) and ordinary yeast. 



He finds that in all cases both bacteria and yeasts are concerned. The 

 bacteria are in such cases mostly lactic bacteria which produce no gas, and do 

 not contribute to the raising. They do have a decided utility, however, in pre- 

 venting the growth of various putrefying bacteria which are sure to be present 

 and produce trouble if not checked by the development of acid. The author 

 says that in a similar way the growth of the yeast prevents the development of 

 molds which would otherwise produce trouble. The chief difTerence be- 

 tween the bread raising by the use of commercial yeast and the use of 

 leaven is in the quickness and certainty of the results. The yeast contains a 

 larger number of yeast organisms and acts, therefore, more quickly and more 

 surely. As a result, the use of such yeast is rapidly supplanting the older more 

 simple method of raising bread by leaven. But even yet in rural localities the 

 older method is in most common use. Holliger studies also the spontaneous 



