Picture of Gram -ve archaeal cell wall. The image above is 600 pixels across and the original is 2,000 pixels across.
Picture of a generalised Gram negative archaeal cell wall (cf Gram positive archaeal cell wall). The mushroom like structures at the surface represent the S-layer. S-layers
are protein lattices that envelop the cell and confer great strength. They are arranged in a crystalline fashion and are anchored into the underlying cell membrane. Such robust cell walls are crucial for those archaeans (extremophiles) that live in (to us) extreme environments.