On arginine splitting as a taxonomic criterion with special regard to the separation of Aeromonas and Vibrio.

An investigation of various methods and media intended for arginine testing of Aeromonas or Vibrio, showed that the method of Thornley (1960) was superior to the others for this purpose because it showed the best conformity with the established taxonomy of a number of type strains and because it furthermore yielded the lowest percentage of false positive reactions from a number of Aeromonas/Vibrio-suspect strains of marine origin.

A shortcut method for estimation of Escherichia coli in Sewage and receiving water.

A simplified method not yet widespread in Scandinavia for the assessment of E. coli in sewage and recipients with McConkey broth for 24 hours at 44 degrees C is recommended. 87 pairs of samples were examined at 37 degrees C and later at 44 degrees C, and directly at 44 degrees C. Also the reduction of the incubation time from 48 to 24 hours was studied. Direct incubation gave a loss of half a tube per sample, while shortening of the incubation period from 48 to 24 hours gave a smaller loss. The proposed alteration of the procedure for the examination of sewage and recipients means a slight loss of precision but this is more than compensated for by the possibility of examining more samples. The survey of the recipients can therefore be better and the control more effective.