THE EPIFAUNA OF A DEVONIAN SPIRIFERID

A detailed study was made of the organisms found attached to shells of Spinocyrtia iowensis from the Upper Devonian Cedar Valley Limestone of Iowa and adjacent states. Four common symbiotic associates were recognized: two polyzoans, a tabulate coral and a serpulid worm. An account is given of the order in which they usually attached themselves to their host and of their most favoured positions on the shell. The possible inter-relationships between all the organisms concerned are discussed. Several comparisons are made with studies on the epifaunas of present-day organisms.