Table 18.2 Differentiation of the principal genera of lactic acid bacteriaa Cell form and arrangement Genus Cocci in chains or tetrads Homofermentative Streptococcus Enterococcus Lactococcus Pediococcus Heterofermentative Leuconostoc Rods,typically in chains Homofermentative Lactobacillus Heterofermentative Lactobacillus aThe physiology of homofermentative and heterofermentative lactic acid bacteria is cov- ered in Section 14.2. 2012 Pearson Education.Inc