“…Since then much additional evidence has been accumulated confirming the idea that there a re two groups of prokaryotes that are no more related to °ne another than either of them is related to the eucyta (i. e. the nuclear plus the cytoplasmic compartment of the e ukaryotes). This evidence includes comparison of differe nt parts of the translation apparatus (Fox et al, 1982;Matheson and Yaguchi, 1982;Yaguchi et al, 1982;Guptc *, 1984;Kessel and Klink, 1982;Cammarano et al, 1985), of the enzymes involved in replication (Prangishvilli and Zillig, 1984;Forterre et al, 1984;Nakayama et al, 1985;Klimczak et al, 1985) and transcription (Zillig * Paper given at the EMBO Workshop on the Molecular Genetics of Archaebacteria, München-Martinsried, June 23 to 26, 1985Schnabel et al, 1983;Huet et al, 1983;Prangishvilli et al, 1982), of cell wall composition (Kandier, 1982) and membrane structure (review by Langworthy et al, 1982).…”