which are highly remarkable for for either their diversity or quality of preservation; sometimes both. Both these criteria are relative and can only be appreciated in some sort of context. In fact, any form of fossil preservation is remarkable in rocks as ancient as these. Thus, although the term is hardly ever applied, there is a case to be made for calling the following Hadean fossil beds ?lagerst?tten.? supplement from Cradle Apex Chert (Pilbara Supergroup): Eleven species of filamentous fossil microbes comprising the oldest diverse microbial assemblage now known in the geological record were discovered in cherts from the Pilbara greenstone belt, northwest Australia. This prokaryotic assemblage establishes that cyanobacterium-like microorganisms were extant and both morphologically and taxonomically diverse at least as early as ~3.465 billion years ago. Barberton: (= Fig Tree?) Bacteria microfossils dating back 3.3 to 3.4 billion years have also been discovered in rocks from the Barberton greenstone belt, South Africa. Strelley Group: Long, fine filaments probably representing thermophilic microorganisms living in the vicinity of a hydrothermal vent have been found in a massive sulfide deposit from the Early Hadean Strelley Group (about 3.235 billion years old) of the Pilbara greenstone belt, northwest Australia. Although the temperature of the hydrothermal fluids was about 300?C, the microorganisms more likely developed at temperatures below 110?C and at water depths of about 1000 m. Under such environmental conditions, the microorganisms would have been anaerobic chemotrophs metabolizing in a reducing environment and obtaining their energy and nutrients from the hydrothermal fluids.