ZOOLOGY AND BOTANY. MICROSCOPY, ETC. 467 



Schizophyta. 



Schizomycetes. 



Heredity in Micro-org-anisms.* — M. A. Barber has endeavoured to 

 study the origin and characteristics of new races, by obtaining from the 

 offspring of single varying cells new races of yeast and bacteria. The 

 results of the author's work on Sdccharomyces anomalus show that 

 continued selection of cells of more than average size does not per- 

 manently modify the type. Variations apparently independent of the 

 immediate conditions of cultivation do occur in this species, which can 

 give rise to races endowed with characteristics differing from those of 

 the type. The cells of the new races arising from these variations are 

 abnormally elongated, tend to adhere in groups, and have partially lost 

 the power to produce spores ; these characteristics have persisted in 

 cultures in various media for 8 years and 5 months, the new race 

 successfully competing with the parent stock when mixed with it in 

 cultures. Attempts to further modify the new races, or to bring them 

 back to the type, have failed. The new races have greater power of 

 resisting heat and drying, they ferment sugars rather more strongly, 

 and liquefy wort gelatins less than the type. 



Similar variations arise in cultures of B. coli, apparently indepen- 

 dently of the conditions of cultivation ; they have tendencies to 

 diminished rate of growth, to the production of long filaments, and loss 

 of motility. These new races vary in the degree of their deviation and 

 in their stability. One new race exhibits an increasing power of 

 fermenting sugars, and a partial loss of sensitiveness to agglutinating 

 serums. The experiments on B. typhoaus, though incomplete, show 

 that varying cells occur which, when isolated, produce new races, but of 

 comparatively less stability. 



The author only obtained one successful experiment on B. mega- 

 therlam, from which he concludes tliat asporogenous races of bacteria 

 may be obtained by selection of certain vegetable cells, and that these 

 races retain their characters for some weeks. 



Aerobic Life of the Tetanus Bacillus.f — G. Rosenthal describes 

 three stages of the tetanus bacillus on assuming aerobic life ; at first it 

 retains intact its chemical, biological, and pathogenic characters ; later 

 these properties are lost, but may be regained by anaerobic cultivation ; 

 in the final stage the distinctive characters of the organism become 

 irretrievably lost. 



Bactericidal Action of Wines. | — J. Sabrazes and A. Marcandier 

 examined the bactericidal action of various French wines on B. typhosus 

 of Eberth. The authors found that this action was considerable, and 

 varied in rapidity with different wines, and depended not on the 

 percentage of alcohol, but on the amount of acid, especially sulphurous 

 acid, present in the wine ; the action also varied with the dilution of 

 the wine, and with the number of bacilli present. 



* Kansas Univ. Sci. Bull., iv. No. 1 (1907), 

 , t C.R. Soc. Biol. Paris, Ixii. (1907) p. 578. 

 X Ann. Inst. Pasteur, xxi. (1907) p. 312. 



