Abstract
It is concluded from a study of the morphological and cultural characters of 60 strains of Döderlein's vaginal bacillus that the organism belongs to the lacto-bacillus group of bacteria.Primary culture of Döderlein's bacillus may be readily obtained on lactose blood agar incubated aerobically provided the vaginal flora is of “Grade A” type, but its subsequent propagation on artificial culture media is less likely to be successful.Three morphological types of Döderlein's bacillus are recognised. Cultural and fermentative tests show that these types are all biologically similar.There is no serological homogeneity among the strains of Döderlein's bacillus, although there was some evidence of a serological relationship among the members of the commonest morphological type. The same serological type tends to persist in the vagina throughout pregnancy. Döderlein's bacillus and lacto-bacilli derived from other sources are not serologically identical.