402 m m \ l; V OF CURRENT RESEARCHES RELATING TO 



Schizophyta. 

 Schizomycetes. 



Distribution of Paratyphoid Bacilli.*— Before the year 1907, there 

 were no differences of opinion as to the conditions under which para- 

 typhoid bacilli were found. It was considered that these organisms were 

 invariably pathogenic, incapable of existing as saprophytes. Since that 

 time, however, many authorities have abandoned this position, and 

 claim for these organisms a very wide distribution in nature. In this 

 present paper, Aumann has made a solid contribution to the settlement 

 of tlir problem. After a resume of the work that has been done in 

 Germany upon this class of organisms, he describes the researches 

 carried out by himself at Hamburg and elsewhere. The material avail- 

 able ((insisted of various foodstuffs, ice, specimens of urine and faeces 

 from men and animals ; in all, about nine thousand examinations were 

 made. He concludes from these investigations that paratyphoid bacilli 

 have no saprophytic phase of existence. These organisms are pathogenic 

 in animals as well as to man, and are not uncommonly found in 

 slaughtered animals. Paratyphoid carriers probably are of frequent 

 occurrence among these animals, and more particularly among such 

 indiscriminate feeders as swine. The isolation of these organisms from 

 Bausages and such articles of diet has therefore an importance which 

 musi lie interpreted in accordance with these results. | 



Acetobacter melanogenum.j — M. W. Beijerinck gives an account of 

 this organism, one of the group of acetic bacteria, which has the property 

 of producing a pigment, by means of which light beer is made dark. If 

 a tiask of ibis darkening beer is kept undisturbed for some days, a 

 pellicle forms, from which cultivations upon beer-wort gelatin plates 

 show the presence of peculiar brown colonies, with a clear margin and a 

 deeply pigmented centre. This growth only takes place upon media 

 which contain glucose or maltose. The chromogen which causes this 

 pigmentation is an aromatic substance, which is burned black in the 

 presence of iron salts. It also reduces alkaline silver and mercurial 

 solutions and turns them black. It differs in some respects from true 

 oxydases and peroxydases. Cultivation and the reaction with iron salts 

 are best shown upon a culture medium containing agar, glucose, peptone, 

 potassium phosphate, iron citrate, and chalk. After twenty-four hours 

 incubation at 30°, the black pigment is clearly seen. It may also be 

 demonstrated by omitting the iron salt from the original medium and 

 adding ii whin growth has taken place. 



Agglutination of Micrococcus melitensis by Normal Sera.}— L. 

 Negre | its out that, under certain conditions, normal sera will -agglu- 

 tinate the organism of Malta fever, and diagnostic errors may arise in 

 ,llls way. In a dilution of 1 : 30, at :;7 Q., agglutination may be 

 produced ; ii can always he observed after 4 or 5^hours with a Micro- 

 Bcope, often even with the naked eye. At room-temperature agglutina- 

 te Lte Abt. Orig. lvii. (1911) pp. 310-46. 

 • + Op \!>t.. xxix. (191] ) pp. my-76. 



C.R.. Soc. Biol. Paris, lxix. (1910) pp. 564 



