116 



Journal of Applied Microscopy. 



perience leads him to believe that these 

 plates can be successfully used to col- 

 lect pond life by leaving them a greater 

 or less time suj)merged in the pond. It 

 first occurred to him that the gelatin 

 might attract these forms for food pur- 

 poses only, but this would hardly 

 answer for the appearance of the 

 larger forms, even though he tried to 

 collect them on other surfaces with 

 little success. 



Micro-Organisms of Industrial Fermenta- 

 tions.* 



Jorgensen's work on micrb-organisms 

 has not only won for itself a place in the 

 Danish language, but the English and 

 Germaft as well. The fact that a re- 

 vised third edition appeared in 1893, and 

 the fourth in 1898, speaks well for the 

 work. The subject matter receives the 

 same general treatment as in former edi- 

 tions. The alcoholic ferments receive 

 special consideration, especially the 

 true yeasts with endogenous spores; also 

 other yeasts, bacteria, and moulds injur- 

 ious to the process of brev/ing are 

 treated. The last chapter deals with the 

 practical application of the question. 

 L. H. Pammel. 



♦Die Mikro-organlsmen der Gahrungsin- 

 dustrie Vlerte, neubearbeite und vermehrte 

 Auflage Berlin, 3+349. 1898. 



Migula's System of Bacteria.* 



The Migula book is the most import- 

 ant which made its appearance during 

 the past year, and, regardless of the 

 opinions expressed, it is certain to 

 become classical. A short review can- 

 not do justice to subject matter which 

 has not only been well selected, but 

 the author has thoroughly searched 

 the literature of European works, 

 which will make it invaluable as 

 a reference work. American litera- 

 ture has been somewhat neglected. The 

 book is divided into the three parts: I, 

 Historical development, page 50; 11, 

 Morphology and Development, pages 50 

 to 237; III, Biological Characters, pages 

 242 to 361. In the chapter on pleomor- 

 phism, the author agrees with Wino- 

 gradsky that pleomorphism, under cul- 

 tural conditions, does not occur in bac- 

 teria, but in closing the chapter he dis- 

 cusses the variability of different organ- 

 isms and states that there are few bac- 

 teria which are of one form (Einfor- 

 mig). The author refers here to varia- 



* System der Bakterien. Handbuch der 

 Morphologie, Entwickelungsgeschichte und 

 Systematik der Bakterien, Jena 1: 368, 6 pi. 

 1S97.. 



bility of the organism such as occurs in 

 higher plants. The Asiatic cholera spir- 

 illum may be taken as an excellent illus- 

 tration, as showing how variable the 

 species is as to form. He adopts essen- 

 tially the classification elaborated by 

 him in Engler and Prantl Pflanzen 

 familien. 



He refers to Bacillus secales as the 

 Burrill corn disease. Dr. Moore and 

 Theobald Smith have well shown that 

 this organism is identical with the 

 Bacillus cloaceae. 



L. H. Pammel. 



Locating Objects Under the Microscope by 



the Points of a Compass-Dial or 



of a Clock- Face. • 



This obvious expedient is of course 

 known to many; but according to the 

 writer's observation it is adequately used 

 by few if any. It is certainly capable of 

 greatly increased usefulness. Anyone 

 who has seen, as the writer has wit- 

 nessed many times, an experienced and 

 competent microscopist search two or 

 three hours for some special object 

 known to be somewhere amidst the con- 

 fusing abundance on a large mount, and 

 then go off to bed (toward morning) 

 without finding it, will realize the con- 

 venience and importance of having some 

 ever-present means of knowing where to 

 look and how to record the location. 



For locating a certain small object 

 among a large number strewn over a 

 slide, or a structural point in a large sec- 

 tion, for instance, for the sake of being 

 able to find it again or to tell someone 

 else where to find it, the Maltwood 

 finder leaves little to be desired in 

 accuracy: as the object can be directly 

 located in one of the squares of l-50th 

 inch, and by recording the position in the 

 square by tenths, readily estimated by 

 the eye, its location can be almost 

 infallibly determined and recorded to 

 1-500 inch. The records are entered in 

 double lines of figures, as 

 21.6 

 18.4 

 the upper line giving the horizontal and 

 the lower line the vertical reading. But 

 this method, though on the whole the 

 best for fine work, requires a special 

 piece of apparatus which is not incapa- 

 ble of being broken in careless hands, 

 and therefore falls far short of being 

 universally applicable. 



The rough expedient of drawing a 

 circle on the cover-glass, around the 

 object, is also useful in some cases; 

 though much more troublesome and less 

 precise, and wholly inapplicable when 



*From Report of the American Postal 

 Microscopical Club,' Troy, N. Y., 1S98. 



