An order of Schizomycetes, including, according to Migula, four families, the Coccaceæ, Bacteriaceæ, Spirillaceæ, and Chlamydobacteriaceæ.
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n. a large group of bacteria having rigid cell walls; motile types have flagella
Word Usage
"Until recently known simply as 'bacteria', the 2 main groups recognized today are archaeabacteria and eubacteria which differ in the composition of their cell membranes."