Septembeb 19, 1913] 



SCIENCE 



413 



one to three weeks seldom gave us any indications 

 of containing bacteria. The only organism which 

 could be regarded without doubt as coming from 

 the interior of the egg was S. pullorum, and this 

 was always found, when present, in the yolks of 

 both fresh and incubated eggs. The results have 

 been quite different, however, with eggs that were 

 kept in warm, damp places for any length of 

 time, and those which were left for several days 

 under sitting hens. Such eggs, especially the in- 

 fertile, frequently contained bacteria. 



On Antiseptic and Bactericidal Properties of Egg 



White: Joel A. Spekky, 2d, M.S. 



The white of the eggs was aseptically trans- 

 ferred to sterile test tubes in 5 cubic centimeter 

 quantities and then inoculated with various organ- 

 isms. Small amounts of the egg white were intro- 

 duced into dilution flasks and agar plates were 

 made with 0.5 c.c. of the dilution. The egg white 

 showed strong bactericidal properties toward Sub- 

 tilis cereus and megatherium while towards coli, 

 typM, anthrax, Proteus vulgarus, Staphylococcus 

 pyogenes aureus and other organisms the anti- 

 septic action only was noticeable. This was true 

 for the white of fresh eggs and cold-storage eggs 

 not more than nine months old. The action of egg 

 white on putriflcus, malignant edema and symp- 

 tomatic anthrax seemed to be purely antiseptic. 

 The white of eggs which are eleven months old or 

 more showed a tendency to lose these properties. 



SOIL BACTERIOLOGY 



A New Method for the Bacteriological Examina- 

 tion of Soils: P. E. Brown, Iowa State College, 

 Ames, Iowa. 



A brief statement of the situation regarding the 

 bacteriological examination of the soils brings out 

 as salient points that the mere quantitative ex- 

 amination of soils is, of little value from the fer- 

 tility standpoint; that the logical means by which 

 conclusions can be reached concerning the influ- 

 ence of varying bacterial content on crop produc- 

 tion consists of certain groups of organisms as 

 measured by the chemical products of their grovrth 

 and actual crop production; and that a necessity 

 therefore for progress in the work is the formula- 

 tion of satisfactory methods for measuring the 

 activities of certain important groups of soil 

 organisms. A discussion of the methods previ- 

 ously employed while recognizing certain value 

 attached to the results obtained thereby, points 

 out the objections to the solution method 

 and to the use of sterilized or air-dry soil as 



media and the conclusion is reached that fresh 

 soil is the logical medium to be employed. Plots 

 differentiated through special treatment were em- 

 ployed in experiments and satisfactory results 

 were secured using fresh soil with ammonium sul- 

 fate for nitrification and fresh soil with mannite 

 for azofication. For ammonification more diffi- 

 culty was experienced in selecting a suitable ni- 

 trogenous material to permit of "an accumulation 

 of ammonia in sufiicient amounts to be measured. 

 Comparisons of the results obtained using air-dry 

 soil and infusions of fresh soil and dried blood, 

 albumen and casein with those secured using fresh 

 soil and the same nitrogenous materials showed 

 that casein added in solution to fresh soil brought 

 out the greatest differences in the ammonifying 

 power of the soils and possessed also certain other 

 advantages incident to manipulation. The method 

 recommended consists then in testing of fresh soil 

 obtained as described in previous work by the 

 writer, adding a solution of casein for ammonifi- 

 cation, ammonium sulfate for nitrification and 

 mannite for nitrogen fixation. 



A Cultural and Morphological Study of some Azo- 

 tobaoter: Dan H. Jones, Ontario Agricultural 

 College, Canada. 



From various samples of soil taken from the 

 garden of the Ontario Agricultural College, six- 

 teen colonies of Azotohacter were isolated. A 

 study of these cultures extending over two years 

 shows them to comprise four distinct varieties or 

 species. These have been tentatively named Al, 

 A2, A3 and Ai. Al and A2 bear a resemblance 

 to Azotoiacter chroococcum and A3 and A4: bear 

 a resemblance to Azotoiacter agilis, as described 

 by Beyerinck. All cultures in Ashby's solution fix 

 atmospheric nitrogen in the form of nitrates. In 

 young cultures (one to two days old) of each 

 variety, the organism is a short, thick rod with 

 rounded ends, frequently occurring in diplo form 

 and motile by means of peritrichic flagella. At 

 this stage, the internal protoplasm is homogeneous, 

 though occasionally what may be a nucleus in the 

 form of a spherical granule is present, this under- 

 going a fission when the cell divides. When cul- 

 tures are four to five days old, the cells become 

 irregularly spherical, coarsely granular and non- 

 motile. The granules enclosed are spherical, vary 

 in size and number and are often of two kinds. 

 The one kind of granule gives the glycogen reac- 

 tion when treated with iodine-potassium-iodide 

 solution, but is negative to certain anilin dyes, 

 whereas the other kind is negative to the glycogen 



