ZOOLOGY AND BOTANY, MICROSCOPY. ETC. 225 



quantity of acid (0* 097-0* 217 p.c.) is necessary than in pure water and 

 an action of 1 hour's duration. 



Intracellular Constituents of the Typhoid Bacillus.* — Dr. A. Mac- 

 fadyen and S. Eowland describe experiments made for the purpose of 

 studying the properties of intracellular plasma. In the present com- 

 munication they describe certain methods for obtaining the intracellular 

 substance of the typhoid bacillus. One of these was to triturate the 

 organisms with sand, care being taken to keep the cylinder cool. 

 Animals treated with the juice thus obtained developed the Widal re- 

 action very promptly and also became immunised, the protection lasting 

 for about 4 weeks. Apparently there is no close connection between the 

 agglutinins and the bacteriolysins, for an animal might become protected 

 without giving evidence of the Widal reaction and might give a strong 

 reaction though having lost its immunity. 



Another method was to triturate at the temperature of liquid air, the 

 brittleness of the cells at this low temperature permitting disintegration 

 without admixture of sand and thus affording a yield of chemically un- 

 altered cell-plasma. 



In the course of this study it was found that B. typhosus produces a 

 hemolysin in various culture media, and that if it produce a soluble toxin 

 it is of a very mild character or the culture media are unsuitable for its 

 proper development. The principal object of the present preliminary 

 communication is intended to emphasise the importance of attacking the 

 question of immunity from an intracellular standpoint, both as regards 

 the organism and the soil on which it grows. 



Polymorphism of Bacillus radicicola.t — Dr. E. Paratore remarks 

 fhat the root-tubercles of the Leguminosae are altered rootlets, the 

 change being due to the pathogenic action of bacteria. These bacteria 

 after an active life are metamorphosed into bacteroids. The stages of 

 this change were observed in the tubercles of Vicia Faba during the 

 period of fructification. Sections of these tubercles showed, besides 

 normal bacteria, Y-shaped, coralloid and dendritic bacteroids. The 

 bacilli become modified first by increasing in size ; one extremity en- 

 larges and divides dichotomously, producing a Y-form. By repetition of 

 the process the dendritic appearances arise. The internal structure of 

 the bacillus also undergoes a change. The protoplasm becomes granular 

 and finally disintegrated, and in this last condition is absorbed partly by 

 the plant and partly by the still living bacteria. 



Avian Diphtheria. J — C. Guerin communicates the results of an ex- 

 perimental study on the pathogenesis, vaccination, and serotherapy of 

 avian diphtheria. The characters of the microbe worked with were as 

 follows : — A coccobacillus exhibiting oscillatory movements, not staining 

 by Gram's method, not liquefying gelatin, not coagulating or altering 

 the reaction of milk, not growing on naturally acid potato, not forming 

 indol, a potential aerobe and non-aerobe, and exhaling a characteristic 

 odour especially from old cultures. The microbe cannot be included in 

 the Pasteurella group of Lignieres since it is motile, nor in that of the 



* Centralbl. Bakt., I* Abt., xxx. (1901) pp. 753-9. 

 f Malpighia, xv. (1902) pp. 175-7 (1 fig.). 

 X Ann. Inst. Pasteur, xv. (1901) pp. 941-52. 



April 16th, 1902 Q 



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