Abstract

Studies of tetracorals from strata of Early and (mainly) Middle Devonian age in Asturias province (Northern Spain) show them to be most similar to the tetracorals known from the Devonian of the Appalachian geosyncline of North America. Of the twenty seven species determined from the Spanish Devonian, nine are presently known from the Appalachian region. The remaining species have been reported previously from the Devonian of Brittany, Turkey, Bohemia, Morocco, and Russia. Three of the species are distributed throughout the Devonian strata of the world.

Considering geographical distribution of the species, it is striking that affinities of the Early and Middle Devonian tetracorals of northern Spain with those of western Germany, Belgium, and northern France are very limited, as are affinities with Asiatic, Australian, and western American forms. This leads to the conclusion that the Appalachian geosyncline of Early and Middle Devonian time formed a continuation of the Mediterranean faunal province of southern Europe, and that, during these times in the neighbouring region of western Germany and Belgium, a coral fauna developed having its own character, and having nothing in common with the southern one. Recent investigations of echinoderms from the same localities of Spain show also forms in common with those of the Onondaga Limestone of the Devonian strata of New York State.

In contrast, the character of a small coral fauna from Upper Devonian strata of Asturias province indicates that, during this later time, the corals had connections to whole of North America, as well as to the Asiatic Russian geosynclines.