398 BOTANY. 



could not feed, also died of splenic fever. The same observers in a 

 paper on the attenuation of virus and its return to virulence give the 

 results of their researches on the means of reducing the virulence of 

 the microbes, more especially those of chicken cholera and splenic fever. 

 The microbe of the first-named disease does not produce spores when 

 made to grow in a decoction of chicken flesh exposed to the air, and 

 it was possible by successive cultures to produce a microbe which be- 

 came gradually less and less virulent, and at length quite inert when 

 iujected into fowls. The nearly inert solutions when injected into fowls 

 enable them to resist violent attacks of chicken cholera when exposed 

 to the disease. The bacilli of splenic fever, however, when cultivated 

 in fluids exposed to the air generally produce spores which retain for 

 an indefinite period the virulence of the disease. When, however, the 

 temperature is kept as low as 16° 0. or above 40° O.-the filaments of 

 the bacillus grow without producing spores, and by successive cultures 

 under these conditions Pasteur obtained an inert fluid for inoculation 

 in splenic fever. In a later paper in the Comptes Eendus the results 

 of inoculations in splenic fever made at Pouilly le Fort, near Melun, 

 are given, and the results show that the animals inoculated did not 

 contract the fever when exposed, while non-inoculated animals did. 

 Chaveau, also in Comptes Eendus, gives his results with regard to in- 

 oculation in splenic fever, which was followed by exemption from the 

 disease; but his injecting fluid he obtains in a different way from Pas- 

 teur, making use of fluids in which only a minute number of bacilli are 

 found, and he believes that the virulence depends on the amount of ba- 

 cillus present. 



In Nuovi studi sulla natura della malaria Cuboni and Marchiafava 

 confirm the views of Tommasi-Crudelli, that the disease is caused by a 

 Bacillus, and state that during the fever only free spores are found in 

 the blood, while during the chill there is a large mass of Bacilli to be 

 seen. In the Proc. Phil. Acad, is a preliminary notice by Dr. H. C. 

 Wood, and in the Bulletin of the National Board of Health, No. 17, is a 

 detailed account by Drs. Wood and Formad on the cause of diphtheria. 

 They find microcci in the membrane of diphtheria which are not to be 

 distinguished from those found in pseudo-membranous trachitis, arising 

 from various causes, but on the whole are inclined to admit the 

 agency of the microcci, at least to a certain extent, in causing diph- 

 theria. In a paper by Dr. Sternberg on a Fatal Form of Septicmmia^ 

 in the rabbit, produced by the subcutaneous injection of humausaliva, 

 he states that he has demonstrated by repeated experiments that his 

 saliva in doses of 1.25 c. c. to 1.75 c. c. injected into the subcutaneous 

 tissue of a rabbit infallibly produces death, which he thinks is owing to 

 the presence of a Micrococcus which closely resembles, if it is not iden- 

 tical with, Micrococcus septicus Cohn. The Eeport of the Department 

 of Agriculture for 1880 contains several elaborate illustrated papers on 

 diseases of domestic animals, with accounts and figures of the organ- 



