ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 391 



producing bacillus (? described by Matchek in 1S87), and (2) a short 

 bacillus which produced an extremely foetid odour in all ordinary culture 

 media. Both organisms are described as Gram-negative and as rapid 

 liquefiers of gelatin. 



Studies in Bacterial Variation.* — P. Eisenberg deals in these (the 

 fourth and fifth) communications with the variations observed with 

 Bacillus prodigiosus and B. violaceus, and with the mutations in the 

 fluorescens and Friedlander groups, Sarcina tetragena and Bacillus 

 typhosus. By growing B. prodigiosus on ordinary media and on media 

 containing fuchsin, crystal-violet, safranin, and so forth, he was able 

 to breed out twenty-two different mutants, which could be distinguished 

 from one another by their chromogenesis (dark red to colourless), and by 

 physical characters, such as size, opacity or translucency, sliminess, etc. 

 The mutations originated more quickly in old cultures, and in greater 

 variety in liquid than on solid media. "With B. violaceus five mutants 

 were bred out, which varied from violet to colourless, the shape of the 

 colonies ranging from compact to spreading forms. In the fluorescens 

 group seven distinct varieties were observed, which differed in their 

 opacity, in their capacity to form pigments (pyocyanin, fluorescin, etc.), 

 and in their ability to produce alkaline reaction. In the rhinoscleroma 

 and Friedlander groups, the reaction of the medium upon which the 

 bacilli are propagated appears to have marked effect upon their mor- 

 phology ; alkaline media favouring the formation of capsulated bacilli, 

 which lose their capsules when grown in the presence of acids. 



Contribution to the Study of Bacillus salmonicida.f — M. Bornand 

 in this communication confirms the observations of Fehlmann re- 

 garding the morphology, etc., of the pigment-producing bacilli which 

 are met with in " Furunculosis of the Salmonidas." The organisms 

 variously described as Bacillus salmonicida Emerl. & Weibel, B. salmon- 

 icida B. Plehn, B. salmonicida C. Fehl., and B. truttse Marsh, may be 

 regarded as members of the fluorescens group of bacteria, which they 

 strongly resemble, both culturally and morphologically. 



The organisms isolated by the author in Switzerland (Yaud and 

 Berne Cantons) are described as short non-motile bacilli, which change 

 into micrococci when grown in broth or on agar. By sub-culture, how- 

 ever, on trout-blood agar, they regain their original forms and, as has 

 been already noted by Fehlmann, acquire motility when grown on this 

 medium. 



Note on Bacillus perfringens Veillon4 — Mdlle. A. Raphael has 

 studied the symptoms and lesions produced by the injection of active 

 cultures of Bacillus perfringens into guinea-pigs and rabbits. Large 

 doses injected intravenously into the former animals produce arterial 

 depression, stoppage of respiration and haematuria ; post mortem, the 

 abdominal viscera are acutely congested and the blood does not coagulate. 



* Centralbl. Bakt., lte Abt. Orig., lxxiii. (1914) pp. 449-88. 

 t Centralbl. Bakt., lte Abt. Orig., lxxiii. (1914) pp. 355-7. 

 X Ann. Inst. Pasteur, xxviii. (1914) pp. 564-8. 



