Silicified calcareous sphinctozoan sponges are reported from an early Middle Devonian limestone of the McGrath Quadrangle, in west-central Alaska, as the oldest species of that order yet described from North America. The new genus, Hormospongia, and the new species, H. labyrinthica, H. diarteria, and H. accara, are characteristically beaded uniserial to branched sphinctozoans with porous walls and pseudosiphonate central openings. Species are differentiated using size of the sponge, canal patterns, and nature of the labyrinthine reticular filling of the chambers.--Journal abstract.

You do not currently have access to this article.