200 SUMMARY OF CURRENT RESEARCHES RELATING TO 



B. typhosus was produced. The serum also contained group agglutinins 

 for other members of the colon-typhoid group, but had no power of 

 agglutinating the original bacillus. This organism, however, absorbs 

 specific and group agglutinins from homologous and heterologous anti- 

 sera to the same extent as a normal typhoid bacillus. Chemical agglu- 

 tinants act similarly on both strains, though the reaction is slightly 

 delayed in the case of the inagglutinable strain. The inagglutinable 

 bacillus probably owes its peculiarity to some alteration of a physical 

 character rather than to immuno-chemical changes. 



Kurloff Bodies.* — R. Knowles and H. W. Acton discuss the nature 

 of these structures, which are found in the large mononuclear leucocytes 

 of the normal guinea-pig. They refer briefly to the observations of 

 Ehrlich and Lazarus and of Ledingham, who described their minute 

 structure ; of Schilling, who classes them with the chlamydozoa ; and 

 of Ross, who describes a complicated life-history with a free-swimming 

 spirochetal stage. The authors conclude that no reliance can be placed 

 upon the appearances presented by fixed films. No trace of a develop- 

 mental cycle could be detected in Kurloff bodies stained with a dahlia 

 solution and examined on a warm stage. They regard these bodies as 

 vesicular structures of cytoplasmic origin, and refuse to accept the view 

 that they are parasites. 



Brownian Movement of Bacterial Spores. f — J. H. Shaxby and 

 E. Emrys-Roberts in this communication give the first instalment of 

 a series of studies upon the phenomenon of Brownian movement. 

 The paper begins with a review of the work of Wiener, Einstein, and 

 others, from which it appears that the persistent and irregular move- 

 ment of small particles suspended in a fluid is independent of such 

 conditions as vibration, intensity of illumination, and convection currents, 

 but depends only upon the size of the particles and the temperature 

 and viscosity of the fluid in which they are suspended. Einstein's 

 formulas expressing the physical laws governing the phenomena under 

 varying conditions are quoted. The observations of the present authors 

 were carried out upon drops hanging from cover-slips, resting upon 

 slides or enclosed between glass surfaces. It was found that spores (of 

 B. anthracis, B. subtilis, and other organisms) showed no Brownian 

 movement. This immobility was shown to be independent of tempera- 

 ture and to be present in suspensions in water, saline solutions, formol 

 solutions, and glycerin solutions. It was observed with living and dead 

 spores. Acids had no effect, but treatment with antiformin inhibited 

 the immobility, so that Brownian movement comparable with that of 

 ordinary particles was observed. Further study showed that spores 

 came to rest at the air-water interface, showing no movement even in 

 the plane of the interface ; they appear to lie in a veritable skin at the 

 surface of the drop. Brownian movement can only be restored (a) by 

 destruction of the interface by violent stirring, or by converting the 



* Indian Journ. Med. Research, i. (1913) pp. 206-11. 

 t Proc. Roy. Soc, Series A, lxxxix. (1914) pp 544-54. 



