Stromatoporoids are found in which 1) the margins are invaginated so as to include tongues of sediment, 2) there are inclusions of sediment within the coenosteum, 3) both tongues and inclusions occur. These stromatoporoids probably grew under conditions of varying rates of sedimentation. Where the marginal tongues or inclusions of sediment are concentrated on one side of a stromatoporoid, it is suggested that this was the lee side of the growing coenosteum during unidirectional current action. In some cases, growth of the stromatoporoids was such that the specimens are now seen to 'lean' into the direction of the current.
Growth forms of stromatoporoids in the silurian of southern Norway