On the Paratyphoid Group of Bacilli

The Interrelationships between the various members of the B. enteritidis-B. paratyphosus B Group of Bacteria

In a series of investigations on the epidemic spread of bacterial infection among mice (Topley, 1919, 1921), it has repeatedly been noted that, if an epidemic be started among a mouse-population by feeding certain animals on cultures ofB. gaertnerand subsequently introducing other susceptible mice into the cage, a varying proportion of these latter may succumb to infection with an organism morphologically and culturally identical withB. gaertner, but differing sharply from it in regard to its agglutination reactions. This organism has been referred to in previous communications as belonging to theB. suipestifergroup, using that term to includeB. aertryckeand other closely related types.

On the Specificity of Bacterial Mutation, with a Résumé of the Results of an Examination of Bacteria found in Faeces and Urine, which undergo Mutation when grown on Lactose Media

Neisser in 1906 claimed to have discovered an organism which, when grown on lactose-agar, threw off suddenly a new strain capable of fermenting lactose. The identity of the new strain was established by Massini (1907) by many cultural and serological tests, and from that time onwards it has been generally accepted that new bacterial strains of great permanence may arise so suddenly as to justify this type of variation being named “ Mutation.”

The Absorption or Saturation test of Castellani: its applications in Sero-Diagnosis, and in the Recognition of Bacterial Species: A critical review

The Absorption or Saturation Test published by Castellani in 1902 is now becoming more extensively used by serological and bacteriological workers in European and American laboratories. Its use is also essential for the accurate study of certain tropical infections, so that it behoves all tropical workers to be familiar with this test. It is therefore believed that an account of the method together with a general review of the literature of the subject may not be out of place in this Journal.