§16§During the 2nd International Symposium on Fossil Algae, organized by the University P. 〓 29 papers were presented in French, English, or Russian. Among the papers selected originally, 16 were carried out to the final stage by their authors. They are presented here in their stratigraphical order. This selection does not pretend to cover the problem of Phanerozoic stromatolites in its entirety, but relates case histories. This should be the seed for further books analyzing and illus trating the paleoecology, the niche and the features of Phanerozoic stromatolites, namely throughout the Mesozoic and the Paleozoic, where the data are still scarce; this will lead to naturalistic views on the evolutionary features of Post Riphean stromes, and will sharpen tools to interpret their Precambrian ancestors. Let me introduce the papers. CLAUDE L. V. MONTY formalizes two basic types of crypt algal micro structures: §16§ the spongiostromate and the porostromate microstructures respectively; the rise of the latter around the Precambrian/Cambrian boundary represents a very significant step in the evolution of cyano bacterial microstructures and in their interaction with the environment. K. K. VERMA and G. BARMAN present a lower Phanerozoic stroma tolitic assemblage from Rajasthan associated with paralic alluvial fans fed by block faulting. Main stromatolite developments occurred during periods of low sedimentation and negligable tectonics, and formed in very shallow marine water. J. §04§Spongiostromate vs. Porostromate Stromatolites and Oncolites.- Lower Cambrian Stromatolites from Northwest Spain and Their Palaeoenvironmental Significance.- Lower Phanerozoic Stromatolites of Rajasthan, Western India.- Contrasted Occurrence of Eodevonian Stromatolites, Northeastern Armorican Massif, France.- Upper Krol Stromatolites from Nainital Hills, Kumaun Himalaya, India.- Autecology and Development of a Stromatolitic-Bound Phylloid Algal Bioherm, Laborcita Formation (Lower Permian), Sacramento Mountains, New Mexico, U.S.A..- Primary Submarine Cements and Neomorphic Spar in a Stromatolitic-Bound Phylloid Algal Bioherm, Laborcita Formation (Wolfcampian), Sacramento Mountains, New Mexico, U.S.A..- Organism-Sediment Interactions in Stromatolites: an Example from the Upper Triassic of South West Britain.- Lower Cretaceous (Wealdian) Blue-Green Algal Deposits of the Province of Valencia, Eastern Spain.- Possible Microbial Accretions in Cenomanian Mounds, S.E. France.- Illustratio §04§n and Paleoecological Significance of Cretaceous and Eocene Girvanella Limestones from Istria (Yugoslavia, Italy).- Paleogene Nonmarine Algal Deposits of the Ebro Basin, Northeastern Spain.- Stromatolites and Cryptalgal Laminites Associated with Messinian Gypsum of Cyprus.- Morphology, Microfabric and Origin of Stromatolites of the Pleistocene Precursor of the Dead Sea, Israel.- Sub-Recent Manganese-Bearing Stromatolites Along Shorelines of the Dead Sea.- Biogenically Formed Aragonite Concretions in Marine Rivularia.- Evidences for Cyanophyte Origin of Stromatoporoids.
