Abstract
Salmonella hormaechei (XXIX[Vi]:z30, z31) of Monteverde was round to dissociate 2 loss variants represented by the formulas XXIX[Vi] :z30... and XXIX[Vi]:-z31... The 2 variants had no major H antigens in common, but in combination they possessed all the antigens of the parent culture. The variants were apparently stable types which arose through a hitherto undescribed form of variation. The possible bearing of this variation on the origin of Salmonella types is briefly discussed.