SUMMARYWhen several strains of Haemophilus vaginalis were grown on Casman rabbit blood agar, individual morphological and cultural differences were noted between the Amies strains which formed pleomorphic and filamentous organisms and large, umbonate colonies, and the Dukes, Edmunds, King and U/L strains which were microscopically coccobacillary to bacillary, non-filamentous, and formed minute convex smooth colonies. Dukes, Edmunds, King and U/L strains required whole blood for maintenance while a whole blood derivative, e.g. peptic digest or Difco chocolate-yeastolate agar, was sufficient for the maintenance of the Amies strains. Serological studies by tube agglutination, direct, indirect and inhibition immunofluorescent methods showed that Dukes, Edmunds, King and U/L strains reacted in a homologous manner with H . vaginalis antisera nos. 317, 394 and 4984. Amies strains did not react with these antisera. However, Amies strains cross-reacted with H . aegyptius antiserum 1 8 0~, while the Dukes, Edmunds, King and U / L strains did not react with this antiserum.

SUMMARYThe application of immunofluorescent techniques for the detection and identification of Haernophilus vaginalis in vaginal secretions by using fluorescent H . vaginalis antiglobulin (strains nos. 317, 4984) were found to be as specific and sensitive as cultural methods and had the advantage of being simple and rapid.