CapsulesMost procaryotes contain so

Capsules
Most procaryotes contain some sort of a polysaccharide layer outside of the cell wall polymer. In a general sense, this layer is called a capsule. A true capsule is a discrete detectable layer of polysaccharides deposited outside the cell wall. A less discrete structure or matrix which embeds the cells is a called a slime layer or a biofilm. A type of capsule found in bacteria called a glycocalyx is a thin layer of tangled polysaccharide fibers which occurs on surface of cells growing in nature (as opposed to the laboratory). Some microbiologists refer to all capsules as glycocalyx and do not differentiate microcapsules.