Many bacterial species are named after people, either the discoverer or a famous person in the field of microbiology. For example, Salmonella is named after D.E. Salmon, who discovered it (albeit as "Bacillus typhi"). For the generic epithet, all names derived from people must be in the female nominative case, either by changing the ending to -a or to the diminutive -ella, depending on the name. For the specific epithet, the names can be converted into either adjectival form (adding -nus (m.), -na (f.), -num (n.) according to the gender of the genus name) or the genitive of the Latinised name.