628 SUMMARY OF CURRENT RESEARCHES RELATING TO 



fermenting coliforrn bacilli in the drain air bears a direct relation to the 

 abundance of fascal material in the sewage. 



Protective Agents in Meningococcus Infection.* — T. J. Horder 

 and M. H. Gordon have found that there is no evidence of any pro- 

 tective influence exerted by immune sera when lethal doses of the 

 meningococcus were injected into rabbits ; but by employing meningo- 

 coccus vaccination a considerable protection against infection by the 

 same organism was obtained. 



"•to"- 



Gaertner Group of Organisms. - ] - — W. G. Savage shows from his ob- 

 servations that it is convenient to recognise a more exclusive enteritidis 

 group (type organism B. enteritidis Gaertner) as a sub-group of the 

 larger group containing organisms of the Gaertner type. Members of 

 the Gaertner group with the characters of the recognised pathological 

 members of this group are not found in the healthy animal intestines of 

 the ordinary domestic animals used for food ; organisms which super- 

 ficially resemble bacilli of the Gaertner group, both B. paratyphosus (b) 

 and (a), are met with in small numbers ; there is no evidence that these 

 Gaertner simulating organisms found in the healthy intestine, are of any 

 pathological significance ; by extended cultural investigation they can 

 be differentiated from the true meat poisoning bacilli. 



Indirect Denitrifying Bacteria. $ — L. Grimbert and M. Bagros have 

 designated as " indirect denitrifying bacteria " organisms of which B. coli 

 and B. typhosus are types, and which attack nitrates only through the 

 intervention of amines or amide substances ; they cause firstly a 

 reduction of nitrate to nitrite, which then reacts on the amide substance 

 of the medium in which the organism is growing, setting free N and 

 C0 2 . The authors express this by the equation — 



CO (Az H,) 2 + 2 Az 2 H = 4 Az + C0 2 + 3 H 2 0. 



Bacteria Intermediate between Bacillus paratyphosus B and 

 Bacillus typhosus.§ — J. Babes and Feodorasco have isolated from the 

 organs of a patient who died with symptoms of typhoid, two different 

 bacilli which were biologically intermediate between Bacillus para- 

 typhosus B and B. typhosus. Bacillus (1) differed from B. paratyphosus 

 in having no action on neutral red, not producing alkalinity in milk, 

 and not agglutinating with paratyphoid serum. It differs from B. 

 typhosus by the production of gas and late alkalinity in Petruschki's 

 medium, in producing a green colour on artichoke, and in not aggluti- 

 nating with typhoid serum. Bacillus (2) resembles B. paratyphosus, but 

 it produces alkalinity in milk from the commencement; it produces no 

 green colour on artichoke, and is not agglutinated by paratyphoid serum. 

 Two other bacilli resembling B. coli were also isolated. 



Effect of Radium on Bacteria. ||—C. E. Iredell and E. P. Minett 

 exposed cultures of Bacillus pyocyaneus, B. anthracis, B. subtilis, 

 Staphylococcus aureus, B. megatherium, B. coli communis, B. typhosus, 



* Rep. Local Govt. Board, 1907-8, p. 341. t Torn, cit., p. 425. 



% C.R. Soc. Biol., Paris, lxvi. (1909) p. 760. § Tom. cit., p. 787. 



jl Lancet, May 22 (1909) p. 1445. 



