Stromatoporoids are abundant in parts of the Sayabec, St. Leon, and Mont Wissick formations of Wenlock and Ludlow age in eastern Quebec, Canada. The fauna is a mixture of species from Wenlock strata of northern Europe, the Wenlock and Ludlow beds of Baie des Chaleurs, Quebec, and Niagaran rocks of the Great Lakes region. Clathrodictyon crickmayi and Stromatopora prima show the affinity of the fauna to that described by Parka from Baie des Chaleurs. Densastroma astroites indicates a close connection of the fauna with the rocks of Wenlock age in England and the Baltic area. Stromatopora antiqua shows the affinity of the fauna to that of central North America. Ecclimadictyon fastigiatum is a widespread species in all these regions. A new species of Actinodictyon (A. quebecense) is described. Two unnamed species of Stromatopora and Clathrodictyon cf. podolica make up the rest of the fauna.